Surgical stapler having force-based motor control

ABSTRACT

A surgical stapler. The surgical stapler includes a drive system, a handle assembly, an electric motor, a battery and a control system. The drive system includes a movable drive member. The handle assembly includes a frame configured to support the movable drive member. The electric motor is mechanically coupled to the drive system. The battery is electrically couplable to the electric motor. The control system is electrically connected to the electric motor and includes a sensor positioned on the frame. The control system is configured to control the electric motor based on a force applied to the frame by the movable drive member.

BACKGROUND

The invention disclosed herein relates to surgical instruments and, invarious embodiments, to surgical stapling and cutting instruments andstaple cartridges for use therewith.

A stapling instrument can include a pair of cooperating elongate jawmembers, wherein each jaw member can be adapted to be inserted into apatient and positioned relative to tissue that is to be stapled and/orincised. In various embodiments, one of the jaw members can support astaple cartridge with at least two laterally spaced rows of staplescontained therein, and the other jaw member can support an anvil withstaple-forming pockets aligned with the rows of staples in the staplecartridge. Generally, the stapling instrument can further include apusher bar and a knife blade which are slidable relative to the jawmembers to sequentially eject the staples from the staple cartridge viacamming surfaces on the pusher bar and/or camming surfaces on a wedgesled that is pushed by the pusher bar. In at least one embodiment, thecamming surfaces can be configured to activate a plurality of stapledrivers carried by the cartridge and associated with the staples inorder to push the staples against the anvil and form laterally spacedrows of deformed staples in the tissue gripped between the jaw members.In at least one embodiment, the knife blade can trail the cammingsurfaces and cut the tissue along a line between the staple rows.

The foregoing discussion is intended only to illustrate various aspectsof the related art in the field of the invention at the time, and shouldnot be taken as a disavowal of claim scope.

BRIEF DESCRIPTION OF THE DRAWINGS

Various features of the embodiments described herein, together withadvantages thereof, may be understood in accordance with the followingdescription taken in conjunction with the accompanying drawings asfollows:

FIG. 1 is a perspective view of a surgical instrument that has aninterchangeable shaft assembly operably coupled thereto;

FIG. 2 is an exploded assembly view of the interchangeable shaftassembly and surgical instrument of FIG. 1;

FIG. 3 is another exploded assembly view showing portions of theinterchangeable shaft assembly and surgical instrument of FIGS. 1 and 2;

FIG. 4 is an exploded assembly view of a portion of the surgicalinstrument of FIGS. 1-3;

FIG. 5 is a cross-sectional side view of a portion of the surgicalinstrument of FIG. 4 with the firing trigger in a fully actuatedposition;

FIG. 6 is another cross-sectional view of a portion of the surgicalinstrument of FIG. 5 with the firing trigger in an unactuated position;

FIG. 7 is an exploded assembly view of one form of an interchangeableshaft assembly;

FIG. 8 is another exploded assembly view of portions of theinterchangeable shaft assembly of FIG. 7;

FIG. 9 is another exploded assembly view of portions of theinterchangeable shaft assembly of FIGS. 7 and 8;

FIG. 10 is a cross-sectional view of a portion of the interchangeableshaft assembly of FIGS. 7-9;

FIG. 11 is a perspective view of a portion of the shaft assembly ofFIGS. 7-10 with the switch drum omitted for clarity;

FIG. 12 is another perspective view of the portion of theinterchangeable shaft assembly of FIG. 11 with the switch drum mountedthereon;

FIG. 13 is a perspective view of a portion of the interchangeable shaftassembly of FIG. 11 operably coupled to a portion of the surgicalinstrument of FIG. 1 illustrated with the closure trigger thereof in anunactuated position;

FIG. 14 is a right side elevational view of the interchangeable shaftassembly and surgical instrument of FIG. 13;

FIG. 15 is a left side elevational view of the interchangeable shaftassembly and surgical instrument of FIGS. 13 and 14;

FIG. 16 is a perspective view of a portion of the interchangeable shaftassembly of FIG. 11 operably coupled to a portion of the surgicalinstrument of FIG. 1 illustrated with the closure trigger thereof in anactuated position and a firing trigger thereof in an unactuatedposition;

FIG. 17 is a right side elevational view of the interchangeable shaftassembly and surgical instrument of FIG. 16;

FIG. 18 is a left side elevational view of the interchangeable shaftassembly and surgical instrument of FIGS. 16 and 17;

FIG. 18A is a right side elevational view of the interchangeable shaftassembly of FIG. 11 operably coupled to a portion of the surgicalinstrument of FIG. 1 illustrated with the closure trigger thereof in anactuated position and the firing trigger thereof in an actuatedposition;

FIG. 19 is a schematic of a system for powering down an electricalconnector of a surgical instrument handle when a shaft assembly is notcoupled thereto;

FIG. 20 is an exploded view of one aspect of an end effector of thesurgical instrument of FIG. 1;

FIGS. 21A-21B is a circuit diagram of the surgical instrument of FIG. 1spanning two drawings sheets;

FIG. 22 illustrates one instance of a power assembly comprising a usagecycle circuit configured to generate a usage cycle count of the batteryback;

FIG. 23 illustrates one aspect of a process for sequentially energizinga segmented circuit;

FIG. 24 illustrates one aspect of a power segment comprising a pluralityof daisy chained power converters;

FIG. 25 illustrates one aspect of a segmented circuit configured tomaximize power available for critical and/or power intense functions;

FIG. 26 illustrates one aspect of a power system comprising a pluralityof daisy chained power converters configured to be sequentiallyenergized;

FIG. 27 illustrates one aspect of a segmented circuit comprising anisolated control section;

FIG. 28, which is divided into FIGS. 28A and 28B, is a circuit diagramof the surgical instrument of FIG. 1;

FIG. 29 is a block diagram the surgical instrument of FIG. 1illustrating interfaces between the handle assembly 14 and the powerassembly and between the handle assembly 14 and the interchangeableshaft assembly;

FIG. 30 illustrates a simplified representation of various electricalcomponents of a surgical stapler according to various embodiments;

FIG. 31 illustrates a simplified representation of various electricaland mechanical components of the surgical stapler of FIG. 31 accordingto various embodiments;

FIG. 32 illustrates a simplified representation of various embodimentsof a surgical stapler;

FIG. 33 illustrates a simplified representation of various embodimentsof a surgical stapler;

FIG. 34 illustrates a simplified representation of various embodimentsof a surgical stapler;

FIG. 35 illustrates a more detailed representation of a component of thesurgical stapler of FIG. 34 according to various embodiments;

FIG. 36 illustrates a simplified representation of various embodimentsof a surgical stapler; and

FIG. 37 illustrates various embodiments of a method for limiting animpact force applied by a surgical stapler.

Corresponding reference characters indicate corresponding partsthroughout the several views. The exemplifications set out hereinillustrate various embodiments of the invention, in one form, and suchexemplifications are not to be construed as limiting the scope of theinvention in any manner.

DETAILED DESCRIPTION

Applicant of the present application owns the following patentapplications that were filed on even date herewith and which are eachherein incorporated by reference in their respective entireties:

U.S. patent application Ser. No. ______, entitled SURGICAL STAPLERHAVING DOWNSTREAM CURRENT-BASED MOTOR CONTROL; Attorney Docket No.END7660USNP/150095;

U.S. patent application Ser. No. ______, entitled SURGICAL STAPLERHAVING MOTOR CONTROL BASED ON A DRIVE SYSTEM COMPONENT; Attorney DocketNo. END7661USNP/150096;

U.S. patent application Ser. No. ______, entitled SURGICAL STAPLERHAVING TEMPERATURE-BASED MOTOR CONTROL; Attorney Docket No.END7662USNP/150097;

U.S. patent application Ser. No. ______, entitled SURGICAL STAPLERHAVING MAGNETIC FIELD-BASED MOTOR CONTROL; Attorney Docket No.END7663USNP/150098;

U.S. patent application Ser. No. ______, entitled SURGICAL STAPLERHAVING CURRENT MIRROR-BASED MOTOR CONTROL; Attorney Docket No.END7665USNP/150100; and

U.S. patent application Ser. No. ______, entitled SURGICAL STAPLERHAVING MOTOR CONTROL BASED ON AN ELECTRICAL PARAMETER RELATED TO A MOTORCURRENT; Attorney Docket No. END7666USNP/150101.

Applicant of the present application owns the following patentapplications that were filed on Mar. 6, 2015 and which are each hereinincorporated by reference in their respective entireties:

U.S. patent application Ser. No. 14/640,746, entitled POWERED SURGICALINSTRUMENT;

U.S. patent application Ser. No. 14/640,765, entitled SYSTEM FORDETECTING THE MIS-INSERTION OF A STAPLE CARTRIDGE INTO A SURGICALSTAPLER;

U.S. patent application Ser. No. 14/640,780, entitled SURGICALINSTRUMENT COMPRISING A LOCKABLE BATTERY HOUSING;

U.S. patent application Ser. No. 14/640,795, entitled MULTIPLE LEVELTHRESHOLDS TO MODIFY OPERATION OF POWERED SURGICAL INSTRUMENTS;

U.S. patent application Ser. No. 14/640,799, entitled SIGNAL AND POWERCOMMUNICATION SYSTEM POSITIONED ON A ROTATABLE SHAFT;

U.S. patent application Ser. No. 14/640,817, entitled INTERACTIVEFEEDBACK SYSTEM FOR POWERED SURGICAL INSTRUMENTS;

U.S. patent application Ser. No. 14/640,831, entitled MONITORING SPEEDCONTROL AND PRECISION INCREMENTING OF MOTOR FOR POWERED SURGICALINSTRUMENTS;

U.S. patent application Ser. No. 14/640,832, entitled ADAPTIVE TISSUECOMPRESSION TECHNIQUES TO ADJUST CLOSURE RATES FOR MULTIPLE TISSUETYPES;

U.S. patent application Ser. No. 14/640,837, entitled SMART SENSORS WITHLOCAL SIGNAL PROCESSING;

U.S. patent application Ser. No. 14/640,844, entitled CONTROL TECHNIQUESAND SUB-PROCESSOR CONTAINED WITHIN MODULAR SHAFT WITH SELECT CONTROLPROCESSING FROM HANDLE;

U.S. patent application Ser. No. 14/640,859, entitled TIME DEPENDENTEVALUATION OF SENSOR DATA TO DETERMINE STABILITY, CREEP, ANDVISCOELASTIC ELEMENTS OF MEASURES; and

U.S. patent application Ser. No. 14/640,935, entitled OVERLAID MULTISENSOR RADIO FREQUENCY (RF) ELECTRODE SYSTEM TO MEASURE TISSUECOMPRESSION.

Applicant of the present application owns the following patentapplications that were filed on Feb. 27, 2015, and which are each hereinincorporated by reference in their respective entireties:

U.S. patent application Ser. No. 14/633,526, entitled ADAPTABLE SURGICALINSTRUMENT HANDLE;

U.S. patent application Ser. No. 14/633,541, entitled MODULAR STAPLINGASSEMBLY;

U.S. patent application Ser. No. 14/633,542, entitled REINFORCED BATTERYFOR A SURGICAL INSTRUMENT;

U.S. patent application Ser. No. 14/633,546, entitled SURGICAL APPARATUSCONFIGURED TO ASSESS WHETHER A PERFORMANCE PARAMETER OF THE SURGICALAPPARATUS IS WITHIN AN ACCEPTABLE PERFORMANCE BAND;

U.S. patent application Ser. No. 14/633,548, entitled POWER ADAPTER FORA SURGICAL INSTRUMENT;

U.S. patent application Ser. No. 14/633,555, entitled SYSTEM FORMONITORING WHETHER A SURGICAL INSTRUMENT NEEDS TO BE SERVICED;

U.S. patent application Ser. No. 14/633,560, entitled SURGICAL CHARGINGSYSTEM THAT CHARGES AND/OR CONDITIONS ONE OR MORE BATTERIES;

U.S. patent application Ser. No. 14/633,562, entitled SURGICAL APPARATUSCONFIGURED TO TRACK AN END-OF-LIFE PARAMETER;

U.S. patent application Ser. No. 14/633,566, entitled CHARGING SYSTEMTHAT ENABLES EMERGENCY RESOLUTIONS FOR CHARGING A BATTERY; and

U.S. patent application Ser. No. 14/633,576, entitled SURGICALINSTRUMENT SYSTEM COMPRISING AN INSPECTION STATION.

Applicant of the present application owns the following patentapplications that were filed on Dec. 18, 2014 and which are each hereinincorporated by reference in their respective entireties:

U.S. patent application Ser. No. 14/574,478, entitled SURGICALINSTRUMENT SYSTEMS COMPRISING AN ARTICULATABLE END EFFECTOR AND MEANSFOR ADJUSTING THE FIRING STROKE OF A FIRING;

U.S. patent application Ser. No. 14/574,483, entitled SURGICALINSTRUMENT ASSEMBLY COMPRISING LOCKABLE SYSTEMS;

U.S. patent application Ser. No. 14/574,493, entitled SURGICALINSTRUMENT ASSEMBLY COMPRISING A FLEXIBLE ARTICULATION SYSTEM;

U.S. patent application Ser. No. 14/574,500, entitled SURGICALINSTRUMENT ASSEMBLY COMPRISING A LOCKABLE ARTICULATION SYSTEM;

U.S. patent application Ser. No. 14/575,117, entitled SURGICALINSTRUMENTS WITH ARTICULATABLE END EFFECTORS AND MOVABLE FIRING BEAMSUPPORT ARRANGEMENTS;

U.S. patent application Ser. No. 14/575,130, entitled SURGICALINSTRUMENT WITH AN ANVIL THAT IS SELECTIVELY MOVABLE ABOUT A DISCRETENON-MOVABLE AXIS RELATIVE TO A STAPLE CARTRIDGE;

U.S. patent application Ser. No. 14/575,139, entitled DRIVE ARRANGEMENTSFOR ARTICULATABLE SURGICAL INSTRUMENTS;

U.S. patent application Ser. No. 14/575,143, entitled SURGICALINSTRUMENTS WITH IMPROVED CLOSURE ARRANGEMENTS;

U.S. patent application Ser. No. 14/575,148, entitled LOCKINGARRANGEMENTS FOR DETACHABLE SHAFT ASSEMBLIES WITH ARTICULATABLE SURGICALEND EFFECTORS; and

U.S. patent application Ser. No. 14/575,154, entitled SURGICALINSTRUMENTS WITH ARTICULATABLE END EFFECTORS AND IMPROVED FIRING BEAMSUPPORT ARRANGEMENTS.

Applicant of the present application also owns the following patentapplications that were filed on Sep. 5, 2014 and which are each hereinincorporated by reference in their respective entireties:

U.S. patent application Ser. No. 14/478,895, entitled MULTIPLE SENSORSWITH ONE SENSOR AFFECTING A SECOND SENSOR'S OUTPUT OR INTERPRETATION;

U.S. patent application Ser. No. 14/478,908, entitled MONITORING DEVICEDEGRADATION BASED ON COMPONENT EVALUATION;

U.S. patent application Ser. No. 14/479,098, entitled SMART CARTRIDGEWAKE UP OPERATION AND DATA RETENTION;

U.S. patent application Ser. No. 14/479,103, entitled CIRCUITRY ANDSENSORS FOR POWERED MEDICAL DEVICE;

U.S. patent application Ser. No. 14/479,108, entitled LOCAL DISPLAY OFTISSUE PARAMETER STABILIZATION;

U.S. patent application Ser. No. 14/479,110, entitled USE OF POLARITY OFHALL MAGNET DETECTION TO DETECT MISLOADED CARTRIDGE;

U.S. patent application Ser. No. 14/479,115, entitled MULTIPLE MOTORCONTROL FOR POWERED MEDICAL DEVICE; and

U.S. patent application Ser. No. 14/479,119, entitled ADJUNCT WITHINTEGRATED SENSORS TO QUANTIFY TISSUE COMPRESSION.

Applicant of the present application also owns the following patentapplications that were filed on Apr. 9, 2014 and which are each hereinincorporated by reference in their respective entireties:

U.S. patent application Ser. No. 14/248,581, entitled SURGICALINSTRUMENT COMPRISING A CLOSING DRIVE AND A FIRING DRIVE OPERATED FROMTHE SAME ROTATABLE OUTPUT, now U.S. Patent Application Publication No.2014/0305989;

U.S. patent application Ser. No. 14/248,584, entitled MODULAR MOTORDRIVEN SURGICAL INSTRUMENTS WITH ALIGNMENT FEATURES FOR ALIGNING ROTARYDRIVE SHAFTS WITH SURGICAL END EFFECTOR SHAFTS, now U.S. PatentApplication Publication No. 2014/0305994;

U.S. patent application Ser. No. 14/248,586, entitled DRIVE SYSTEMDECOUPLING ARRANGEMENT FOR A SURGICAL INSTRUMENT, now U.S. PatentApplication Publication No. 2014/0305990;

U.S. patent application Ser. No. 14/248,587, entitled POWERED SURGICALSTAPLER, now U.S. Patent Application Publication No. 2014/0309665;

U.S. patent application Ser. No. 14/248,588, entitled POWERED LINEARSURGICAL STAPLER, now U.S. Patent Application Publication No.2014/0309666;

U.S. patent application Ser. No. 14/248,590, entitled MOTOR DRIVENSURGICAL INSTRUMENTS WITH LOCKABLE DUAL DRIVE SHAFTS, now U.S. PatentApplication Publication No. 2014/0305987;

U.S. patent application Ser. No. 14/248,591, entitled TRANSMISSIONARRANGEMENT FOR A SURGICAL INSTRUMENT, now U.S. Patent ApplicationPublication No. 2014/0305991;

U.S. patent application Ser. No. 14/248,595, entitled SURGICALINSTRUMENT SHAFT INCLUDING SWITCHES FOR CONTROLLING THE OPERATION OF THESURGICAL INSTRUMENT, now U.S. Patent Application Publication No.2014/0305988; and

U.S. patent application Ser. No. 14/248,607, entitled MODULAR MOTORDRIVEN SURGICAL INSTRUMENTS WITH STATUS INDICATION ARRANGEMENTS, nowU.S.

Patent Application Publication No. 2014/0305992.

Applicant of the present application also owns the following patentapplications that were filed on Mar. 26, 2014 and are each hereinincorporated by reference in their respective entireties:

U.S. patent application Ser. No. 14/226,071, entitled SURGICALINSTRUMENT CONTROL CIRCUIT HAVING A SAFETY PROCESSOR;

U.S. patent application Ser. No. 14/226,075, entitled MODULAR POWEREDSURGICAL INSTRUMENT WITH DETACHABLE SHAFT ASSEMBLIES;

U.S. patent application Ser. No. 14/226,076, entitled POWER MANAGEMENTTHROUGH SEGMENTED CIRCUIT AND VARIABLE VOLTAGE PROTECTION;

U.S. patent application Ser. No. 14/226,081, entitled SYSTEMS ANDMETHODS FOR CONTROLLING A SEGMENTED CIRCUIT;

U.S. patent application Ser. No. 14/226,093, entitled FEEDBACKALGORITHMS FOR MANUAL BAILOUT SYSTEMS FOR SURGICAL INSTRUMENTS;

U.S. patent application Ser. No. 14/226,094, entitled VERIFICATION OFNUMBER OF BATTERY EXCHANGES/PROCEDURE COUNT;

U.S. patent application Ser. No. 14/226,097, entitled SURGICALINSTRUMENT COMPRISING INTERACTIVE SYSTEMS;

U.S. patent application Ser. No. 14/226,099, entitled STERILIZATIONVERIFICATION CIRCUIT;

U.S. patent application Ser. No. 14/226,106, entitled POWER MANAGEMENTCONTROL SYSTEMS FOR SURGICAL INSTRUMENTS;

U.S. patent application Ser. No. 14/226,111, entitled SURGICAL STAPLINGINSTRUMENT SYSTEM;

U.S. patent application Ser. No. 14/226,116, entitled SURGICALINSTRUMENT UTILIZING SENSOR ADAPTATION;

U.S. patent application Ser. No. 14/226,117, entitled POWER MANAGEMENTTHROUGH SLEEP OPTIONS OF SEGMENTED CIRCUIT AND WAKE UP CONTROL;

U.S. patent application Ser. No. 14/226,125, entitled SURGICALINSTRUMENT COMPRISING A ROTATABLE SHAFT;

U.S. patent application Ser. No. 14/226,126, entitled INTERFACE SYSTEMSFOR USE WITH SURGICAL INSTRUMENTS; and

U.S. patent application Ser. No. 14/226,133, entitled MODULAR SURGICALINSTRUMENT SYSTEM.

Applicant of the present application also owns the following patentapplication that was filed on Mar. 7, 2014 and is herein incorporated byreference in its entirety:

U.S. patent application Ser. No. 14/200,111, entitled CONTROL SYSTEMSFOR SURGICAL INSTRUMENTS, now U.S. Patent Application Publication No.2014/0263539.

Applicant of the present application also owns the following patentapplications that were filed on Apr. 16, 2013 and which are each hereinincorporated by reference in their respective entireties:

U.S. Provisional Patent Application Ser. No. 61/812,365, entitledSURGICAL INSTRUMENT WITH MULTIPLE FUNCTIONS PERFORMED BY A SINGLE MOTOR;

U.S. Provisional Patent Application Ser. No. 61/812,372, entitledSURGICAL INSTRUMENT WITH MULTIPLE FUNCTIONS PERFORMED BY A SINGLE MOTOR;

U.S. Provisional Patent Application Ser. No. 61/812,376, entitled LINEARCUTTER WITH POWER;

U.S. Provisional Patent Application Ser. No. 61/812,382, entitled LINEARCUTTER WITH MOTOR AND PISTOL GRIP; and

U.S. Provisional Patent Application Ser. No. 61/812,385, entitledSURGICAL INSTRUMENT HANDLE WITH MULTIPLE ACTUATION MOTORS AND MOTORCONTROL.

Applicant of the present application also owns the following patentapplications that were filed on Mar. 14, 2013 and which are each hereinincorporated by reference in their respective entireties:

U.S. patent application Ser. No. 13/803,053, entitled INTERCHANGEABLESHAFT ASSEMBLIES FOR USE WITH A SURGICAL INSTRUMENT, now U.S. PatentApplication Publication No. 2014/0263564;

U.S. patent application Ser. No. 13/803,066, entitled DRIVE SYSTEMLOCKOUT ARRANGEMENTS FOR MODULAR SURGICAL INSTRUMENTS, now U.S. PatentApplication Publication No. 2014/0263565;

U.S. patent application Ser. No. 13/803,086, entitled ARTICULATABLESURGICAL INSTRUMENT COMPRISING AN ARTICULATION LOCK, now U.S. PatentApplication Publication No. 2014/0263541;

U.S. patent application Ser. No. 13/803,097, entitled ARTICULATABLESURGICAL INSTRUMENT COMPRISING A FIRING DRIVE, now U.S. PatentApplication Publication No. 2014/0263542;

U.S. patent application Ser. No. 13/803,117, entitled ARTICULATIONCONTROL SYSTEM FOR ARTICULATABLE SURGICAL INSTRUMENTS, now U.S. PatentApplication Publication No. 2014/0263553;

U.S. patent application Ser. No. 13/803,130, entitled DRIVE TRAINCONTROL ARRANGEMENTS FOR MODULAR SURGICAL INSTRUMENTS, now U.S. PatentApplication Publication No. 2014/0263543;

U.S. patent application Ser. No. 13/803,148, entitled MULTI-FUNCTIONMOTOR FOR A SURGICAL INSTRUMENT, now U.S. Patent Application PublicationNo. 2014/0263554;

U.S. patent application Ser. No. 13/803,159, entitled METHOD AND SYSTEMFOR OPERATING A SURGICAL INSTRUMENT, now U.S. Patent ApplicationPublication No. 2014/0277017;

U.S. patent application Ser. No. 13/803,193, entitled CONTROLARRANGEMENTS FOR A DRIVE MEMBER OF A SURGICAL INSTRUMENT, now U.S.Patent Application Publication No. 2014/0263537; and

U.S. patent application Ser. No. 13/803,210, entitled SENSORARRANGEMENTS FOR ABSOLUTE POSITIONING SYSTEM FOR SURGICAL INSTRUMENTS,now U.S. Patent Application Publication No. 2014/0263538.

Applicant of the present application owns the following patentapplications that were filed on Mar. 1, 2013 and which are each hereinincorporated by reference in their respective entireties:

U.S. patent application Ser. No. 13/782,295, entitled ARTICULATABLESURGICAL INSTRUMENTS WITH CONDUCTIVE PATHWAYS FOR SIGNAL COMMUNICATION,now U.S. Patent Application Publication No. 2014/0246471;

U.S. patent application Ser. No. 13/782,323, entitled ROTARY POWEREDARTICULATION JOINTS FOR SURGICAL INSTRUMENTS, now U.S. PatentApplication Publication No. 2014/0246472;

U.S. patent application Ser. No. 13/782,338, entitled THUMBWHEEL SWITCHARRANGEMENTS FOR SURGICAL INSTRUMENTS, now U.S. Patent ApplicationPublication No. 2014/0249557;

U.S. patent application Ser. No. 13/782,358, entitled JOYSTICK SWITCHASSEMBLIES FOR SURGICAL INSTRUMENTS, now U.S. Patent ApplicationPublication No. 2014/0246477;

U.S. patent application Ser. No. 13/782,375, entitled ROTARY POWEREDSURGICAL INSTRUMENTS WITH MULTIPLE DEGREES OF FREEDOM, now U.S. PatentApplication Publication No. 2014/0246473;

U.S. patent application Ser. No. 13/782,460, entitled MULTIPLE PROCESSORMOTOR CONTROL FOR MODULAR SURGICAL INSTRUMENTS, now U.S. PatentApplication Publication No. 2014/0246478;

U.S. patent application Ser. No. 13/782,481, entitled SENSORSTRAIGHTENED END EFFECTOR DURING REMOVAL THROUGH TROCAR, now U.S. PatentApplication Publication No. 2014/0246479;

U.S. patent application Ser. No. 13/782,499, entitled ELECTROMECHANICALSURGICAL DEVICE WITH SIGNAL RELAY ARRANGEMENT, now U.S. PatentApplication Publication No. 2014/0246474;

U.S. patent application Ser. No. 13/782,518, entitled CONTROL METHODSFOR SURGICAL INSTRUMENTS WITH REMOVABLE IMPLEMENT PORTIONS, now U.S.Patent Application Publication No. 2014/0246475; and

U.S. patent application Ser. No. 13/782,536, entitled SURGICALINSTRUMENT SOFT STOP, now U.S. Patent Application Publication No.2014/0246476.

Numerous specific details are set forth to provide a thoroughunderstanding of the overall structure, function, manufacture, and useof the embodiments as described in the specification and illustrated inthe accompanying drawings. Well-known operations, components, andelements have not been described in detail so as not to obscure theembodiments described in the specification. The reader will understandthat the embodiments described and illustrated herein are non-limitingexamples, and thus it can be appreciated that the specific structuraland functional details disclosed herein may be representative andillustrative. Variations and changes thereto may be made withoutdeparting from the scope of the claims.

The terms “comprise” (and any form of comprise, such as “comprises” and“comprising”), “have” (and any form of have, such as “has” and“having”), “include” (and any form of include, such as “includes” and“including”) and “contain” (and any form of contain, such as “contains”and “containing”) are open-ended linking verbs. As a result, a surgicalsystem, device, or apparatus that “comprises,” “has,” “includes” or“contains” one or more elements possesses those one or more elements,but is not limited to possessing only those one or more elements.Likewise, an element of a system, device, or apparatus that “comprises,”“has,” “includes” or “contains” one or more features possesses those oneor more features, but is not limited to possessing only those one ormore features.

The terms “proximal” and “distal” are used herein with reference to aclinician manipulating the handle portion of the surgical instrument.The term “proximal” referring to the portion closest to the clinicianand the term “distal” referring to the portion located away from theclinician. It will be further appreciated that, for convenience andclarity, spatial terms such as “vertical”, “horizontal”, “up”, and“down” may be used herein with respect to the drawings. However,surgical instruments are used in many orientations and positions, andthese terms are not intended to be limiting and/or absolute.

Various exemplary devices and methods are provided for performinglaparoscopic and minimally invasive surgical procedures. However, thereader will readily appreciate that the various methods and devicesdisclosed herein can be used in numerous surgical procedures andapplications including, for example, in connection with open surgicalprocedures. As the present Detailed Description proceeds, the readerwill further appreciate that the various instruments disclosed hereincan be inserted into a body in any way, such as through a naturalorifice, through an incision or puncture hole formed in tissue, etc. Theworking portions or end effector portions of the instruments can beinserted directly into a patient's body or can be inserted through anaccess device that has a working channel through which the end effectorand elongated shaft of a surgical instrument can be advanced.

A surgical stapling system can comprise a shaft and an end effectorextending from the shaft. The end effector comprises a first jaw and asecond jaw. The first jaw comprises a staple cartridge. The staplecartridge is insertable into and removable from the first jaw; however,other embodiments are envisioned in which a staple cartridge is notremovable from, or at least readily replaceable from, the first jaw. Thesecond jaw comprises an anvil configured to deform staples ejected fromthe staple cartridge. The second jaw is pivotable relative to the firstjaw about a closure axis; however, other embodiments are envisioned inwhich first jaw is pivotable relative to the second jaw. The surgicalstapling system further comprises an articulation joint configured topermit the end effector to be rotated, or articulated, relative to theshaft. The end effector is rotatable about an articulation axisextending through the articulation joint. Other embodiments areenvisioned which do not include an articulation joint.

The staple cartridge comprises a cartridge body. The cartridge bodyincludes a proximal end, a distal end, and a deck extending between theproximal end and the distal end. In use, the staple cartridge ispositioned on a first side of the tissue to be stapled and the anvil ispositioned on a second side of the tissue. The anvil is moved toward thestaple cartridge to compress and clamp the tissue against the deck.Thereafter, staples removably stored in the cartridge body can bedeployed into the tissue. The cartridge body includes staple cavitiesdefined therein wherein staples are removably stored in the staplecavities. The staple cavities are arranged in six longitudinal rows.Three rows of staple cavities are positioned on a first side of alongitudinal slot and three rows of staple cavities are positioned on asecond side of the longitudinal slot. Other arrangements of staplecavities and staples may be possible.

The staples are supported by staple drivers in the cartridge body. Thedrivers are movable between a first, or unfired position, and a second,or fired, position to eject the staples from the staple cavities. Thedrivers are retained in the cartridge body by a retainer which extendsaround the bottom of the cartridge body and includes resilient membersconfigured to grip the cartridge body and hold the retainer to thecartridge body. The drivers are movable between their unfired positionsand their fired positions by a sled. The sled is movable between aproximal position adjacent the proximal end and a distal positionadjacent the distal end. The sled comprises a plurality of rampedsurfaces configured to slide under the drivers and lift the drivers, andthe staples supported thereon, toward the anvil.

Further to the above, the sled is moved distally by a firing member. Thefiring member is configured to contact the sled and push the sled towardthe distal end. The longitudinal slot defined in the cartridge body isconfigured to receive the firing member. The anvil also includes a slotconfigured to receive the firing member. The firing member furthercomprises a first cam which engages the first jaw and a second cam whichengages the second jaw. As the firing member is advanced distally, thefirst cam and the second cam can control the distance, or tissue gap,between the deck of the staple cartridge and the anvil. The firingmember also comprises a knife configured to incise the tissue capturedintermediate the staple cartridge and the anvil. It is desirable for theknife to be positioned at least partially proximal to the rampedsurfaces such that the staples are ejected ahead of the knife.

FIGS. 1-6 depict a motor-driven surgical cutting and fasteninginstrument 10 that may or may not be reused. In the illustratedexamples, the instrument 10 includes a housing 12 that comprises ahandle assembly 14 that is configured to be grasped, manipulated andactuated by the clinician. The housing 12 is configured for operableattachment to an interchangeable shaft assembly 200 that has a surgicalend effector 300 operably coupled thereto that is configured to performone or more surgical tasks or procedures. As the present DetailedDescription proceeds, it will be understood that the various unique andnovel arrangements of the various forms of interchangeable shaftassemblies disclosed herein also may be effectively employed inconnection with robotically-controlled surgical systems. Thus, the term“housing” also may encompass a housing or similar portion of a roboticsystem that houses or otherwise operably supports at least one drivesystem that is configured to generate and apply at least one controlmotion which could be used to actuate the interchangeable shaftassemblies disclosed herein and their respective equivalents. The term“frame” may refer to a portion of a handheld surgical instrument. Theterm “frame” also may represent a portion of a robotically controlledsurgical instrument and/or a portion of the robotic system that may beused to operably control a surgical instrument. For example, theinterchangeable shaft assemblies disclosed herein may be employed withvarious robotic systems, instruments, components and methods disclosedin U.S. patent application Ser. No. 13/118,241, entitled SURGICALSTAPLING INSTRUMENTS WITH ROTATABLE STAPLE DEPLOYMENT ARRANGEMENTS, nowU.S. Pat. No. 9,072,535. U.S. patent application Ser. No. 13/118,241,entitled SURGICAL STAPLING INSTRUMENTS WITH ROTATABLE STAPLE DEPLOYMENTARRANGEMENTS, now U.S. Pat. No. 9,072,535, is incorporated by referenceherein in its entirety.

The housing 12 depicted in FIGS. 1-3 is shown in connection with aninterchangeable shaft assembly 200 that includes an end effector 300that comprises a surgical cutting and fastening device that isconfigured to operably support a surgical staple cartridge 304 therein.The housing 12 may be configured for use in connection withinterchangeable shaft assemblies that include end effectors that areadapted to support different sizes and types of staple cartridges, havedifferent shaft lengths, sizes, and types, etc. In addition, the housing12 also may be effectively employed with a variety of otherinterchangeable shaft assemblies including those assemblies that areconfigured to apply other motions and forms of energy such as, forexample, radio frequency (RF) energy, ultrasonic energy and/or motion toend effector arrangements adapted for use in connection with varioussurgical applications and procedures. Furthermore, the end effectors,shaft assemblies, handles, surgical instruments, and/or surgicalinstrument systems can utilize any suitable fastener, or fasteners, tofasten tissue. For instance, a fastener cartridge comprising a pluralityof fasteners removably stored therein can be removably inserted intoand/or attached to the end effector of a shaft assembly.

FIG. 1 illustrates the surgical instrument 10 with an interchangeableshaft assembly 200 operably coupled thereto. FIGS. 2 and 3 illustrateattachment of the interchangeable shaft assembly 200 to the housing 12or handle assembly 14. As shown in FIG. 4, the handle assembly 14 maycomprise a pair of interconnectable handle housing segments 16 and 18that may be interconnected by screws, snap features, adhesive, etc. Inthe illustrated arrangement, the handle housing segments 16, 18cooperate to form a pistol grip portion 19 that can be gripped andmanipulated by the clinician. As will be discussed in further detailbelow, the handle assembly 14 operably supports a plurality of drivesystems therein that are configured to generate and apply variouscontrol motions to corresponding portions of the interchangeable shaftassembly that is operably attached thereto.

Referring now to FIG. 4, the handle assembly 14 may further include aframe 20 that operably supports a plurality of drive systems. Forexample, the frame 20 can operably support a “first” or closure drivesystem, generally designated as 30, which may be employed to applyclosing and opening motions to the interchangeable shaft assembly 200that is operably attached or coupled thereto. In at least one form, theclosure drive system 30 may include an actuator in the form of a closuretrigger 32 that is pivotally supported by the frame 20. Morespecifically, as illustrated in FIG. 4, the closure trigger 32 ispivotally coupled to the housing 14 by a pin 33. Such arrangementenables the closure trigger 32 to be manipulated by a clinician suchthat when the clinician grips the pistol grip portion 19 of the handleassembly 14, the closure trigger 32 may be easily pivoted from astarting or “unactuated” position to an “actuated” position and moreparticularly to a fully compressed or fully actuated position. Theclosure trigger 32 may be biased into the unactuated position by springor other biasing arrangement (not shown). In various forms, the closuredrive system 30 further includes a closure linkage assembly 34 that ispivotally coupled to the closure trigger 32. As shown in FIG. 4, theclosure linkage assembly 34 may include a first closure link 36 and asecond closure link 38 that are pivotally coupled to the closure trigger32 by a pin 35. The second closure link 38 also may be referred toherein as an “attachment member” and include a transverse attachment pin37.

Still referring to FIG. 4, it can be observed that the first closurelink 36 may have a locking wall or end 39 thereon that is configured tocooperate with a closure release assembly 60 that is pivotally coupledto the frame 20. In at least one form, the closure release assembly 60may comprise a release button assembly 62 that has a distally protrudinglocking pawl 64 formed thereon. The release button assembly 62 may bepivoted in a counterclockwise direction by a release spring (not shown).As the clinician depresses the closure trigger 32 from its unactuatedposition towards the pistol grip portion 19 of the handle assembly 14,the first closure link 36 pivots upward to a point wherein the lockingpawl 64 drops into retaining engagement with the locking wall 39 on thefirst closure link 36 thereby preventing the closure trigger 32 fromreturning to the unactuated position. See FIG. 18. Thus, the closurerelease assembly 60 serves to lock the closure trigger 32 in the fullyactuated position. When the clinician desires to unlock the closuretrigger 32 to permit it to be biased to the unactuated position, theclinician simply pivots the closure release button assembly 62 such thatthe locking pawl 64 is moved out of engagement with the locking wall 39on the first closure link 36. When the locking pawl 64 has been movedout of engagement with the first closure link 36, the closure trigger 32may pivot back to the unactuated position. Other closure trigger lockingand release arrangements also may be employed.

Further to the above, FIGS. 13-15 illustrate the closure trigger 32 inits unactuated position which is associated with an open, or unclamped,configuration of the shaft assembly 200 in which tissue can bepositioned between the jaws of the shaft assembly 200. FIGS. 16-18illustrate the closure trigger 32 in its actuated position which isassociated with a closed, or clamped, configuration of the shaftassembly 200 in which tissue is clamped between the jaws of the shaftassembly 200. Upon comparing FIGS. 14 and 17, the reader will appreciatethat, when the closure trigger 32 is moved from its unactuated position(FIG. 14) to its actuated position (FIG. 17), the closure release button62 is pivoted between a first position (FIG. 14) and a second position(FIG. 17). The rotation of the closure release button 62 can be referredto as being an upward rotation; however, at least a portion of theclosure release button 62 is being rotated toward the circuit board 100.Referring to FIG. 4, the closure release button 62 can include an arm 61extending therefrom and a magnetic element 63, such as a permanentmagnet, for example, mounted to the arm 61. When the closure releasebutton 62 is rotated from its first position to its second position, themagnetic element 63 can move toward the circuit board 100. The circuitboard 100 can include at least one sensor configured to detect themovement of the magnetic element 63. In at least one aspect, a magneticfield sensor 65, for example, can be mounted to the bottom surface ofthe circuit board 100. The magnetic field sensor 65 can be configured todetect changes in a magnetic field surrounding the magnetic field sensor65 caused by the movement of the magnetic element 63. The magnetic fieldsensor 65 can be in signal communication with a microcontroller 1500(FIG. 19), for example, which can determine whether the closure releasebutton 62 is in its first position, which is associated with theunactuated position of the closure trigger 32 and the open configurationof the end effector, its second position, which is associated with theactuated position of the closure trigger 32 and the closed configurationof the end effector, and/or any position between the first position andthe second position.

As used throughout the present disclosure, a magnetic field sensor maybe a Hall effect sensor, search coil, fluxgate, optically pumped,nuclear precession, SQUID, Hall-effect, anisotropic magnetoresistance,giant magnetoresistance, magnetic tunnel junctions, giantmagnetoimpedance, magnetostrictive/piezoelectric composites,magnetodiode, magnetotransistor, fiber optic, magnetooptic, andmicroelectromechanical systems-based magnetic sensors, among others.

In at least one form, the handle assembly 14 and the frame 20 mayoperably support another drive system referred to herein as a firingdrive system 80 that is configured to apply firing motions tocorresponding portions of the interchangeable shaft assembly attachedthereto. The firing drive system may 80 also be referred to herein as a“second drive system”. The firing drive system 80 may employ an electricmotor 82, located in the pistol grip portion 19 of the handle assembly14. In various forms, the motor 82 may be a DC brushed driving motorhaving a maximum rotation of, approximately, 25,000 RPM, for example. Inother arrangements, the motor 82 may include a brushless motor, acordless motor, a synchronous motor, a stepper motor, or any othersuitable electric motor. The motor 82 may be powered by a power source90 that in one form may comprise a removable power pack 92. As shown inFIG. 4, for example, the power pack 92 may comprise a proximal housingportion 94 that is configured for attachment to a distal housing portion96. The proximal housing portion 94 and the distal housing portion 96are configured to operably support a plurality of batteries 98 therein.Batteries 98 may each comprise, for example, a Lithium Ion (“LI”) orother suitable battery. The distal housing portion 96 is configured forremovable operable attachment to a control circuit board assembly 100which is also operably coupled to the motor 82. A number of batteries 98may be connected in series may be used as the power source for thesurgical instrument 10. In addition, the power source 90 may bereplaceable and/or rechargeable.

As outlined above with respect to other various forms, the electricmotor 82 can include a rotatable shaft (not shown) that operablyinterfaces with a gear reducer assembly 84 that is mounted in meshingengagement with a with a set, or rack, of drive teeth 122 on alongitudinally-movable drive member 120. In use, a voltage polarityprovided by the power source 90 can operate the electric motor 82 in aclockwise direction wherein the voltage polarity applied to the electricmotor by the battery can be reversed in order to operate the electricmotor 82 in a counter-clockwise direction. When the electric motor 82 isrotated in one direction, the drive member 120 will be axially driven inthe distal direction “DD”. When the motor 82 is driven in the oppositerotary direction, the drive member 120 will be axially driven in aproximal direction “PD”. The handle assembly 14 can include a switchwhich can be configured to reverse the polarity applied to the electricmotor 82 by the power source 90. As with the other forms describedherein, the handle assembly 14 can also include a sensor that isconfigured to detect the position of the drive member 120 and/or thedirection in which the drive member 120 is being moved.

Actuation of the motor 82 can be controlled by a firing trigger 130 thatis pivotally supported on the handle assembly 14. The firing trigger 130may be pivoted between an unactuated position and an actuated position.The firing trigger 130 may be biased into the unactuated position by aspring 132 or other biasing arrangement such that when the clinicianreleases the firing trigger 130, it may be pivoted or otherwise returnedto the unactuated position by the spring 132 or biasing arrangement. Inat least one form, the firing trigger 130 can be positioned “outboard”of the closure trigger 32 as was discussed above. In at least one form,a firing trigger safety button 134 may be pivotally mounted to theclosure trigger 32 by pin 35. The safety button 134 may be positionedbetween the firing trigger 130 and the closure trigger 32 and have apivot arm 136 protruding therefrom. See FIG. 4. When the closure trigger32 is in the unactuated position, the safety button 134 is contained inthe handle assembly 14 where the clinician cannot readily access it andmove it between a safety position preventing actuation of the firingtrigger 130 and a firing position wherein the firing trigger 130 may befired. As the clinician depresses the closure trigger 32, the safetybutton 134 and the firing trigger 130 pivot down wherein they can thenbe manipulated by the clinician.

As discussed above, the handle assembly 14 can include a closure trigger32 and a firing trigger 130. Referring to FIGS. 14-18A, the firingtrigger 130 can be pivotably mounted to the closure trigger 32. Theclosure trigger 32 can include an arm 31 extending therefrom and thefiring trigger 130 can be pivotably mounted to the arm 31 about a pivotpin 33. When the closure trigger 32 is moved from its unactuatedposition (FIG. 14) to its actuated position (FIG. 17), the firingtrigger 130 can descend downwardly, as outlined above. After the safetybutton 134 has been moved to its firing position, referring primarily toFIG. 18A, the firing trigger 130 can be depressed to operate the motorof the surgical instrument firing system. In various instances, thehandle assembly 14 can include a tracking system, such as system 800,for example, configured to determine the position of the closure trigger32 and/or the position of the firing trigger 130. With primary referenceto FIGS. 14, 17, and 18A, the tracking system 800 can include a magneticelement, such as permanent magnet 802, for example, which is mounted toan arm 801 extending from the firing trigger 130. The tracking system800 can comprise one or more sensors, such as a first magnetic fieldsensor 803 and a second magnetic field sensor 804, for example, whichcan be configured to track the position of the magnet 802.

Upon comparing FIGS. 14 and 17, the reader will appreciate that, whenthe closure trigger 32 is moved from its unactuated position to itsactuated position, the magnet 802 can move between a first positionadjacent the first magnetic field sensor 803 and a second positionadjacent the second magnetic field sensor 804.

Upon comparing FIGS. 17 and 18A, the reader will further appreciatethat, when the firing trigger 130 is moved from an unfired position(FIG. 17) to a fired position (FIG. 18A), the magnet 802 can moverelative to the second magnetic field sensor 804. The sensors 803 and804 can track the movement of the magnet 802 and can be in signalcommunication with a microcontroller on the circuit board 100. With datafrom the first sensor 803 and/or the second sensor 804, themicrocontroller can determine the position of the magnet 802 along apredefined path and, based on that position, the microcontroller candetermine whether the closure trigger 32 is in its unactuated position,its actuated position, or a position therebetween. Similarly, with datafrom the first sensor 803 and/or the second sensor 804, themicrocontroller can determine the position of the magnet 802 along apredefined path and, based on that position, the microcontroller candetermine whether the firing trigger 130 is in its unfired position, itsfully fired position, or a position therebetween.

As indicated above, in at least one form, the longitudinally movabledrive member 120 has a rack of teeth 122 formed thereon for meshingengagement with a corresponding drive gear 86 of the gear reducerassembly 84. At least one form also includes a manually-actuatable“bailout” assembly 140 that is configured to enable the clinician tomanually retract the longitudinally movable drive member 120 should themotor 82 become disabled. The bailout assembly 140 may include a leveror bailout handle assembly 142 that is configured to be manually pivotedinto ratcheting engagement with teeth 124 also provided in the drivemember 120. Thus, the clinician can manually retract the drive member120 by using the bailout handle assembly 142 to ratchet the drive member120 in the proximal direction “PD”. U.S. Patent Application PublicationNo. 2010/0089970, now U.S. Pat. No. 8,608,045, discloses bailoutarrangements and other components, arrangements and systems that alsomay be employed with the various instruments disclosed herein. U.S.patent application Ser. No. 12/249,117, entitled POWERED SURGICALCUTTING AND STAPLING APPARATUS WITH MANUALLY RETRACTABLE FIRING SYSTEM,U.S. Patent Application Publication No. 2010/0089970, now U.S. Pat. No.8,608,045, is hereby incorporated by reference in its entirety.

Turning now to FIGS. 1 and 7, the interchangeable shaft assembly 200includes a surgical end effector 300 that comprises an elongated channel302 that is configured to operably support a staple cartridge 304therein. The end effector 300 may further include an anvil 306 that ispivotally supported relative to the elongated channel 302. Theinterchangeable shaft assembly 200 may further include an articulationjoint 270 and an articulation lock 350 (FIG. 8) which can be configuredto releasably hold the end effector 300 in a desired position relativeto a shaft axis SA-SA. Details regarding the construction and operationof the end effector 300, the articulation joint 270 and the articulationlock 350 are set forth in U.S. patent application Ser. No. 13/803,086,filed Mar. 14, 2013, entitled ARTICULATABLE SURGICAL INSTRUMENTCOMPRISING AN ARTICULATION LOCK, now U.S. Patent Application PublicationNo. 2014/0263541. The entire disclosure of U.S. patent application Ser.No. 13/803,086, filed Mar. 14, 2013, entitled ARTICULATABLE SURGICALINSTRUMENT COMPRISING AN ARTICULATION LOCK, now U.S. Patent ApplicationPublication No. 2014/0263541, is hereby incorporated by referenceherein. As shown in FIGS. 7 and 8, the interchangeable shaft assembly200 can further include a proximal housing or nozzle 201 comprised ofnozzle portions 202 and 203. The interchangeable shaft assembly 200 canfurther include a closure tube 260 which can be utilized to close and/oropen the anvil 306 of the end effector 300. Primarily referring now toFIGS. 8 and 9, the shaft assembly 200 can include a spine 210 which canbe configured to fixably support a shaft frame portion 212 of thearticulation lock 350. See FIG. 8. The spine 210 can be configured to,one, slidably support a firing member 220 therein and, two, slidablysupport the closure tube 260 which extends around the spine 210. Thespine 210 can also be configured to slidably support a proximalarticulation driver 230. The articulation driver 230 has a distal end231 that is configured to operably engage the articulation lock 350. Thearticulation lock 350 interfaces with an articulation frame 352 that isadapted to operably engage a drive pin (not shown) on the end effectorframe (not shown). As indicated above, further details regarding theoperation of the articulation lock 350 and the articulation frame may befound in U.S. patent application Ser. No. 13/803,086, now U.S. PatentApplication Publication No. 2014/0263541. In various circumstances, thespine 210 can comprise a proximal end 211 which is rotatably supportedin a chassis 240. In one arrangement, for example, the proximal end 211of the spine 210 has a thread 214 formed thereon for threaded attachmentto a spine bearing 216 configured to be supported within the chassis240. See FIG. 7. Such an arrangement facilitates rotatable attachment ofthe spine 210 to the chassis 240 such that the spine 210 may beselectively rotated about a shaft axis SA-SA relative to the chassis240.

Referring primarily to FIG. 7, the interchangeable shaft assembly 200includes a closure shuttle 250 that is slidably supported within thechassis 240 such that it may be axially moved relative thereto. As shownin FIGS. 3 and 7, the closure shuttle 250 includes a pair ofproximally-protruding hooks 252 that are configured for attachment tothe attachment pin 37 that is attached to the second closure link 38 aswill be discussed in further detail below. A proximal end 261 of theclosure tube 260 is coupled to the closure shuttle 250 for relativerotation thereto. For example, a U shaped connector 263 is inserted intoan annular slot 262 in the proximal end 261 of the closure tube 260 andis retained within vertical slots 253 in the closure shuttle 250. SeeFIG. 7. Such an arrangement serves to attach the closure tube 260 to theclosure shuttle 250 for axial travel therewith while enabling theclosure tube 260 to rotate relative to the closure shuttle 250 about theshaft axis SA-SA. A closure spring 268 is journaled on the closure tube260 and serves to bias the closure tube 260 in the proximal direction“PD” which can serve to pivot the closure trigger into the unactuatedposition when the shaft assembly is operably coupled to the handleassembly 14.

In at least one form, the interchangeable shaft assembly 200 may furtherinclude an articulation joint 270. Other interchangeable shaftassemblies, however, may not be capable of articulation. As shown inFIG. 7, for example, the articulation joint 270 includes a double pivotclosure sleeve assembly 271. According to various forms, the doublepivot closure sleeve assembly 271 includes an end effector closuresleeve assembly 272 having upper and lower distally projecting tangs273, 274. An end effector closure sleeve assembly 272 includes ahorseshoe aperture 275 and a tab 276 for engaging an opening tab on theanvil 306 in the various manners described in U.S. patent applicationSer. No. 13/803,086, filed Mar. 14, 2013, entitled ARTICULATABLESURGICAL INSTRUMENT COMPRISING AN ARTICULATION LOCK, now U.S. PatentApplication Publication No. 2014/0263541, which has been incorporated byreference herein. As described in further detail therein, the horseshoeaperture 275 and tab 276 engage a tab on the anvil when the anvil 306 isopened. An upper double pivot link 277 includes upwardly projectingdistal and proximal pivot pins that engage respectively an upper distalpin hole in the upper proximally projecting tang 273 and an upperproximal pin hole in an upper distally projecting tang 264 on theclosure tube 260. A lower double pivot link 278 includes upwardlyprojecting distal and proximal pivot pins that engage respectively alower distal pin hole in the lower proximally projecting tang 274 and alower proximal pin hole in the lower distally projecting tang 265. Seealso FIG. 8.

In use, the closure tube 260 is translated distally (direction “DD”) toclose the anvil 306, for example, in response to the actuation of theclosure trigger 32. The anvil 306 is closed by distally translating theclosure tube 260 and thus the shaft closure sleeve assembly 272, causingit to strike a proximal surface on the anvil 360 in the manner describedin the aforementioned reference U.S. patent application Ser. No.13/803,086, now U.S. Patent Application Publication No. 2014/0263541. Aswas also described in detail in that reference, the anvil 306 is openedby proximally translating the closure tube 260 and the shaft closuresleeve assembly 272, causing tab 276 and the horseshoe aperture 275 tocontact and push against the anvil tab to lift the anvil 306. In theanvil-open position, the shaft closure tube 260 is moved to its proximalposition.

As indicated above, the surgical instrument 10 may further include anarticulation lock 350 of the types and construction described in furtherdetail in U.S. patent application Ser. No. 13/803,086, now U.S. PatentApplication Publication No. 2014/0263541, which can be configured andoperated to selectively lock the end effector 300 in position. Sucharrangement enables the end effector 300 to be rotated, or articulated,relative to the shaft closure tube 260 when the articulation lock 350 isin its unlocked state. In such an unlocked state, the end effector 300can be positioned and pushed against soft tissue and/or bone, forexample, surrounding the surgical site within the patient in order tocause the end effector 300 to articulate relative to the closure tube260. The end effector 300 also may be articulated relative to theclosure tube 260 by an articulation driver 230.

As was also indicated above, the interchangeable shaft assembly 200further includes a firing member 220 that is supported for axial travelwithin the shaft spine 210. The firing member 220 includes anintermediate firing shaft portion 222 that is configured for attachmentto a distal cutting portion or knife bar 280. The firing member 220 alsomay be referred to herein as a “second shaft” and/or a “second shaftassembly”. As shown in FIGS. 8 and 9, the intermediate firing shaftportion 222 may include a longitudinal slot 223 in the distal endthereof which can be configured to receive a tab 284 on the proximal end282 of the distal knife bar 280. The longitudinal slot 223 and theproximal end 282 can be sized and configured to permit relative movementtherebetween and can comprise a slip joint 286. The slip joint 286 canpermit the intermediate firing shaft portion 222 of the firing drive 220to be moved to articulate the end effector 300 without moving, or atleast substantially moving, the knife bar 280. Once the end effector 300has been suitably oriented, the intermediate firing shaft portion 222can be advanced distally until a proximal sidewall of the longitudinalslot 223 comes into contact with the tab 284 in order to advance theknife bar 280 and fire the staple cartridge positioned within thechannel 302 As can be further seen in FIGS. 8 and 9, the shaft spine 210has an elongate opening or window 213 therein to facilitate assembly andinsertion of the intermediate firing shaft portion 222 into the shaftframe 210. Once the intermediate firing shaft portion 222 has beeninserted therein, a top frame segment 215 may be engaged with the shaftframe 212 to enclose the intermediate firing shaft portion 222 and knifebar 280 therein. Further description of the operation of the firingmember 220 may be found in U.S. patent application Ser. No. 13/803,086,now U.S. Patent Application Publication No. 2014/0263541.

Further to the above, the shaft assembly 200 can include a clutchassembly 400 which can be configured to selectively and releasablycouple the articulation driver 230 to the firing member 220. In oneform, the clutch assembly 400 includes a lock collar, or sleeve 402,positioned around the firing member 220 wherein the lock sleeve 402 canbe rotated between an engaged position in which the lock sleeve 402couples the articulation driver 360 to the firing member 220 and adisengaged position in which the articulation driver 360 is not operablycoupled to the firing member 200. When lock sleeve 402 is in its engagedposition, distal movement of the firing member 220 can move thearticulation driver 360 distally and, correspondingly, proximal movementof the firing member 220 can move the articulation driver 230proximally. When lock sleeve 402 is in its disengaged position, movementof the firing member 220 is not transmitted to the articulation driver230 and, as a result, the firing member 220 can move independently ofthe articulation driver 230. In various circumstances, the articulationdriver 230 can be held in position by the articulation lock 350 when thearticulation driver 230 is not being moved in the proximal or distaldirections by the firing member 220.

Referring primarily to FIG. 9, the lock sleeve 402 can comprise acylindrical, or an at least substantially cylindrical, body including alongitudinal aperture 403 defined therein configured to receive thefiring member 220. The lock sleeve 402 can comprisediametrically-opposed, inwardly-facing lock protrusions 404 and anoutwardly-facing lock member 406. The lock protrusions 404 can beconfigured to be selectively engaged with the firing member 220. Moreparticularly, when the lock sleeve 402 is in its engaged position, thelock protrusions 404 are positioned within a drive notch 224 defined inthe firing member 220 such that a distal pushing force and/or a proximalpulling force can be transmitted from the firing member 220 to the locksleeve 402. When the lock sleeve 402 is in its engaged position, thesecond lock member 406 is received within a drive notch 232 defined inthe articulation driver 230 such that the distal pushing force and/orthe proximal pulling force applied to the lock sleeve 402 can betransmitted to the articulation driver 230. In effect, the firing member220, the lock sleeve 402, and the articulation driver 230 will movetogether when the lock sleeve 402 is in its engaged position. On theother hand, when the lock sleeve 402 is in its disengaged position, thelock protrusions 404 may not be positioned within the drive notch 224 ofthe firing member 220 and, as a result, a distal pushing force and/or aproximal pulling force may not be transmitted from the firing member 220to the lock sleeve 402. Correspondingly, the distal pushing force and/orthe proximal pulling force may not be transmitted to the articulationdriver 230. In such circumstances, the firing member 220 can be slidproximally and/or distally relative to the lock sleeve 402 and theproximal articulation driver 230.

As shown in FIGS. 8-12, the shaft assembly 200 further includes a switchdrum 500 that is rotatably received on the closure tube 260. The switchdrum 500 comprises a hollow shaft segment 502 that has a shaft boss 504formed thereon for receive an outwardly protruding actuation pin 410therein. In various circumstances, the actuation pin 410 extends througha slot 267 into a longitudinal slot 408 provided in the lock sleeve 402to facilitate axial movement of the lock sleeve 402 when it is engagedwith the articulation driver 230. A rotary torsion spring 420 isconfigured to engage the boss 504 on the switch drum 500 and a portionof the nozzle housing 203 as shown in FIG. 10 to apply a biasing forceto the switch drum 500. The switch drum 500 can further comprise atleast partially circumferential openings 506 defined therein which,referring to FIGS. 5 and 6, can be configured to receive circumferentialmounts 204, 205 extending from the nozzle halves 202, 203 and permitrelative rotation, but not translation, between the switch drum 500 andthe proximal nozzle 201. As shown in those Figures, the mounts 204 and205 also extend through openings 266 in the closure tube 260 to beseated in recesses 209 in the shaft spine 210. However, rotation of thenozzle 201 to a point where the mounts 204, 205 reach the end of theirrespective slots 506 in the switch drum 500 will result in rotation ofthe switch drum 500 about the shaft axis SA-SA. Rotation of the switchdrum 500 will ultimately result in the rotation of the actuation pin 410and the lock sleeve 402 between its engaged and disengaged positions.Thus, in essence, the nozzle 201 may be employed to operably engage anddisengage the articulation drive system with the firing drive system inthe various manners described in further detail in U.S. patentapplication Ser. No. 13/803,086, now U.S. Patent Application PublicationNo. 2014/0263541.

As also illustrated in FIGS. 8-12, the shaft assembly 200 can comprise aslip ring assembly 600 which can be configured to conduct electricalpower to and/or from the end effector 300 and/or communicate signals toand/or from the end effector 300, for example. The slip ring assembly600 can comprise a proximal connector flange 604 mounted to a chassisflange 242 extending from the chassis 240 and a distal connector flange601 positioned within a slot defined in the shaft housings 202, 203. Theproximal connector flange 604 can comprise a first face and the distalconnector flange 601 can comprise a second face which is positionedadjacent to and movable relative to the first face. The distal connectorflange 601 can rotate relative to the proximal connector flange 604about the shaft axis SA-SA. The proximal connector flange 604 cancomprise a plurality of concentric, or at least substantiallyconcentric, conductors 602 defined in the first face thereof. Aconnector 607 can be mounted on the proximal side of the connectorflange 601 and may have a plurality of contacts (not shown) wherein eachcontact corresponds to and is in electrical contact with one of theconductors 602. Such an arrangement permits relative rotation betweenthe proximal connector flange 604 and the distal connector flange 601while maintaining electrical contact therebetween. The proximalconnector flange 604 can include an electrical connector 606 which canplace the conductors 602 in signal communication with a shaft circuitboard 610 mounted to the shaft chassis 240, for example. In at least oneinstance, a wiring harness comprising a plurality of conductors canextend between the electrical connector 606 and the shaft circuit board610. The electrical connector 606 may extend proximally through aconnector opening 243 defined in the chassis mounting flange 242. SeeFIG. 7. U.S. patent application Ser. No. 13/800,067, entitled STAPLECARTRIDGE TISSUE THICKNESS SENSOR SYSTEM, filed on Mar. 13, 2013, nowU.S. Patent Application Publication No. 2014/0263552, is incorporated byreference in its entirety. U.S. patent application Ser. No. 13/800,025,entitled STAPLE CARTRIDGE TISSUE THICKNESS SENSOR SYSTEM, filed on Mar.13, 2013, now U.S. Patent Application Publication No. 2014/0263551, isincorporated by reference in its entirety. Further details regardingslip ring assembly 600 may be found in U.S. patent application Ser. No.13/803,086, now U.S. Patent Application Publication No. 2014/0263541.

As discussed above, the shaft assembly 200 can include a proximalportion which is fixably mounted to the handle assembly 14 and a distalportion which is rotatable about a longitudinal axis. The rotatabledistal shaft portion can be rotated relative to the proximal portionabout the slip ring assembly 600, as discussed above. The distalconnector flange 601 of the slip ring assembly 600 can be positionedwithin the rotatable distal shaft portion. Moreover, further to theabove, the switch drum 500 can also be positioned within the rotatabledistal shaft portion. When the rotatable distal shaft portion isrotated, the distal connector flange 601 and the switch drum 500 can berotated synchronously with one another. In addition, the switch drum 500can be rotated between a first position and a second position relativeto the distal connector flange 601. When the switch drum 500 is in itsfirst position, the articulation drive system may be operably disengagedfrom the firing drive system and, thus, the operation of the firingdrive system may not articulate the end effector 300 of the shaftassembly 200. When the switch drum 500 is in its second position, thearticulation drive system may be operably engaged with the firing drivesystem and, thus, the operation of the firing drive system mayarticulate the end effector 300 of the shaft assembly 200. When theswitch drum 500 is moved between its first position and its secondposition, the switch drum 500 is moved relative to distal connectorflange 601. In various instances, the shaft assembly 200 can comprise atleast one sensor configured to detect the position of the switch drum500. Turning now to FIGS. 11 and 12, the distal connector flange 601 cancomprise a magnetic field sensor 605, for example, and the switch drum500 can comprise a magnetic element, such as permanent magnet 505, forexample. The magnetic field sensor 605 can be configured to detect theposition of the permanent magnet 505. When the switch drum 500 isrotated between its first position and its second position, thepermanent magnet 505 can move relative to the magnetic field sensor 605.In various instances, magnetic field sensor 605 can detect changes in amagnetic field created when the permanent magnet 505 is moved. Themagnetic field sensor 605 can be in signal communication with the shaftcircuit board 610 and/or the handle circuit board 100, for example.Based on the signal from the magnetic field sensor 605, amicrocontroller on the shaft circuit board 610 and/or the handle circuitboard 100 can determine whether the articulation drive system is engagedwith or disengaged from the firing drive system.

Referring again to FIGS. 3 and 7, the chassis 240 includes at least one,and preferably two, tapered attachment portions 244 formed thereon thatare adapted to be received within corresponding dovetail slots 702formed within a distal attachment flange portion 700 of the frame 20.Each dovetail slot 702 may be tapered or, stated another way, besomewhat V-shaped to seatingly receive the attachment portions 244therein. As can be further seen in FIGS. 3 and 7, a shaft attachment lug226 is formed on the proximal end of the intermediate firing shaft 222.As will be discussed in further detail below, when the interchangeableshaft assembly 200 is coupled to the handle assembly 14, the shaftattachment lug 226 is received in a firing shaft attachment cradle 126formed in the distal end 125 of the longitudinal drive member 120 asshown in FIGS. 3 and 6, for example.

Various shaft assemblies employ a latch system 710 for removablycoupling the shaft assembly 200 to the housing 12 and more specificallyto the frame 20. As shown in FIG. 7, for example, in at least one form,the latch system 710 includes a lock member or lock yoke 712 that ismovably coupled to the chassis 240. In the illustrated example, forexample, the lock yoke 712 has a U-shape with two spaced downwardlyextending legs 714. The legs 714 each have a pivot lug 715 formedthereon that are adapted to be received in corresponding holes 245formed in the chassis 240. Such arrangement facilitates pivotalattachment of the lock yoke 712 to the chassis 240. The lock yoke 712may include two proximally protruding lock lugs 716 that are configuredfor releasable engagement with corresponding lock detents or grooves 704in the distal attachment flange 700 of the frame 20. See FIG. 3. Invarious forms, the lock yoke 712 is biased in the proximal direction byspring or biasing member (not shown). Actuation of the lock yoke 712 maybe accomplished by a latch button 722 that is slidably mounted on alatch actuator assembly 720 that is mounted to the chassis 240. Thelatch button 722 may be biased in a proximal direction relative to thelock yoke 712. As will be discussed in further detail below, the lockyoke 712 may be moved to an unlocked position by biasing the latchbutton the in distal direction which also causes the lock yoke 712 topivot out of retaining engagement with the distal attachment flange 700of the frame 20. When the lock yoke 712 is in “retaining engagement”with the distal attachment flange 700 of the frame 20, the lock lugs 716are retainingly seated within the corresponding lock detents or grooves704 in the distal attachment flange 700.

When employing an interchangeable shaft assembly that includes an endeffector of the type described herein that is adapted to cut and fastentissue, as well as other types of end effectors, it may be desirable toprevent inadvertent detachment of the interchangeable shaft assemblyfrom the housing during actuation of the end effector. For example, inuse the clinician may actuate the closure trigger 32 to grasp andmanipulate the target tissue into a desired position. Once the targettissue is positioned within the end effector 300 in a desiredorientation, the clinician may then fully actuate the closure trigger 32to close the anvil 306 and clamp the target tissue in position forcutting and stapling. In that instance, the first drive system 30 hasbeen fully actuated. After the target tissue has been clamped in the endeffector 300, it may be desirable to prevent the inadvertent detachmentof the shaft assembly 200 from the housing 12. One form of the latchsystem 710 is configured to prevent such inadvertent detachment.

As can be most particularly seen in FIG. 7, the lock yoke 712 includesat least one and preferably two lock hooks 718 that are adapted tocontact corresponding lock lug portions 256 that are formed on theclosure shuttle 250. Referring to FIGS. 13-15, when the closure shuttle250 is in an unactuated position (i.e., the first drive system 30 isunactuated and the anvil 306 is open), the lock yoke 712 may be pivotedin a distal direction to unlock the interchangeable shaft assembly 200from the housing 12. When in that position, the lock hooks 718 do notcontact the lock lug portions 256 on the closure shuttle 250. However,when the closure shuttle 250 is moved to an actuated position (i.e., thefirst drive system 30 is actuated and the anvil 306 is in the closedposition), the lock yoke 712 is prevented from being pivoted to anunlocked position. See FIGS. 16-18. Stated another way, if the clinicianwere to attempt to pivot the lock yoke 712 to an unlocked position or,for example, the lock yoke 712 was in advertently bumped or contacted ina manner that might otherwise cause it to pivot distally, the lock hooks718 on the lock yoke 712 will contact the lock lug portions 256 on theclosure shuttle 250 and prevent movement of the lock yoke 712 to anunlocked position.

Attachment of the interchangeable shaft assembly 200 to the handleassembly 14 will now be described with reference to FIG. 3. To commencethe coupling process, the clinician may position the chassis 240 of theinterchangeable shaft assembly 200 above or adjacent to the distalattachment flange 700 of the frame 20 such that the tapered attachmentportions 244 formed on the chassis 240 are aligned with the dovetailslots 702 in the frame 20. The clinician may then move the shaftassembly 200 along an installation axis IA that is perpendicular to theshaft axis SA-SA to seat the attachment portions 244 in “operableengagement” with the corresponding dovetail receiving slots 702. Indoing so, the shaft attachment lug 226 on the intermediate firing shaft222 will also be seated in the cradle 126 in the longitudinally movabledrive member 120 and the portions of pin 37 on the second closure link38 will be seated in the corresponding hooks 252 in the closure yoke250. As used herein, the term “operable engagement” in the context oftwo components means that the two components are sufficiently engagedwith each other so that upon application of an actuation motion thereto,the components may carry out their intended action, function and/orprocedure.

As discussed above, at least five systems of the interchangeable shaftassembly 200 can be operably coupled with at least five correspondingsystems of the handle assembly 14. A first system can comprise a framesystem which couples and/or aligns the frame or spine of the shaftassembly 200 with the frame 20 of the handle assembly 14. Another systemcan comprise a closure drive system 30 which can operably connect theclosure trigger 32 of the handle assembly 14 and the closure tube 260and the anvil 306 of the shaft assembly 200. As outlined above, theclosure tube attachment yoke 250 of the shaft assembly 200 can beengaged with the pin 37 on the second closure link 38. Another systemcan comprise the firing drive system 80 which can operably connect thefiring trigger 130 of the handle assembly 14 with the intermediatefiring shaft 222 of the shaft assembly 200.

As outlined above, the shaft attachment lug 226 can be operablyconnected with the cradle 126 of the longitudinal drive member 120.Another system can comprise an electrical system which can signal to acontroller in the handle assembly 14, such as microcontroller, forexample, that a shaft assembly, such as shaft assembly 200, for example,has been operably engaged with the handle assembly 14 and/or, two,conduct power and/or communication signals between the shaft assembly200 and the handle assembly 14. For instance, the shaft assembly 200 caninclude an electrical connector 1410 that is operably mounted to theshaft circuit board 610. The electrical connector 1410 is configured formating engagement with a corresponding electrical connector 1400 on thehandle control board 100. Further details regaining the circuitry andcontrol systems may be found in U.S. patent application Ser. No.13/803,086, now U.S. Patent Application Publication No. 2014/0263541,the entire disclosure of which was previously incorporated by referenceherein. The fifth system may consist of the latching system forreleasably locking the shaft assembly 200 to the handle assembly 14.

Referring again to FIGS. 2 and 3, the handle assembly 14 can include anelectrical connector 1400 comprising a plurality of electrical contacts.Turning now to FIG. 19, the electrical connector 1400 can comprise afirst contact 1401 a, a second contact 1401 b, a third contact 1401 c, afourth contact 1401 d, a fifth contact 1401 e, and a sixth contact 1401f, for example. While the illustrated example utilizes six contacts,other examples are envisioned which may utilize more than six contactsor less than six contacts.

As illustrated in FIG. 19, the first contact 1401 a can be in electricalcommunication with a transistor 1408, contacts 1401 b-1401 e can be inelectrical communication with a microcontroller 1500, and the sixthcontact 1401 f can be in electrical communication with a ground. Incertain circumstances, one or more of the electrical contacts 1401b-1401 e may be in electrical communication with one or more outputchannels of the microcontroller 1500 and can be energized, or have avoltage potential applied thereto, when the handle assembly 14 is in apowered state. In some circumstances, one or more of the electricalcontacts 1401 b-1401 e may be in electrical communication with one ormore input channels of the microcontroller 1500 and, when the handleassembly 14 is in a powered state, the microcontroller 1500 can beconfigured to detect when a voltage potential is applied to suchelectrical contacts. When a shaft assembly, such as shaft assembly 200,for example, is assembled to the handle assembly 14, the electricalcontacts 1401 a-1401 f may not communicate with each other. When a shaftassembly is not assembled to the handle assembly 14, however, theelectrical contacts 1401 a-1401 f of the electrical connector 1400 maybe exposed and, in some circumstances, one or more of the contacts 1401a-1401 f may be accidentally placed in electrical communication witheach other. Such circumstances can arise when one or more of thecontacts 1401 a-1401 f come into contact with an electrically conductivematerial, for example. When this occurs, the microcontroller 1500 canreceive an erroneous input and/or the shaft assembly 200 can receive anerroneous output, for example. To address this issue, in variouscircumstances, the handle assembly 14 may be unpowered when a shaftassembly, such as shaft assembly 200, for example, is not attached tothe handle assembly 14.

In other circumstances, the handle assembly 14 can be powered when ashaft assembly, such as shaft assembly 200, for example, is not attachedthereto. In such circumstances, the microcontroller 1500 can beconfigured to ignore inputs, or voltage potentials, applied to thecontacts in electrical communication with the microcontroller 1500,i.e., contacts 1401 b-1401 e, for example, until a shaft assembly isattached to the handle assembly 14. Even though the microcontroller 1500may be supplied with power to operate other functionalities of thehandle assembly 14 in such circumstances, the handle assembly 14 may bein a powered-down state. In a way, the electrical connector 1400 may bein a powered-down state as voltage potentials applied to the electricalcontacts 1401 b-1401 e may not affect the operation of the handleassembly 14. The reader will appreciate that, even though contacts 1401b-1401 e may be in a powered-down state, the electrical contacts 1401 aand 1401 f, which are not in electrical communication with themicrocontroller 1500, may or may not be in a powered-down state. Forinstance, sixth contact 1401 f may remain in electrical communicationwith a ground regardless of whether the handle assembly 14 is in apowered-up or a powered-down state.

Furthermore, the transistor 1408, and/or any other suitable arrangementof transistors, such as transistor 1410, for example, and/or switchesmay be configured to control the supply of power from a power source1404, such as a battery 90 within the handle assembly 14, for example,to the first electrical contact 1401 a regardless of whether the handleassembly 14 is in a powered-up or a powered-down state. In variouscircumstances, the shaft assembly 200, for example, can be configured tochange the state of the transistor 1408 when the shaft assembly 200 isengaged with the handle assembly 14. In certain circumstances, furtherto the below, a magnetic field sensor 1402 can be configured to switchthe state of transistor 1410 which, as a result, can switch the state oftransistor 1408 and ultimately supply power from power source 1404 tofirst contact 1401 a. In this way, both the power circuits and thesignal circuits to the connector 1400 can be powered down when a shaftassembly is not installed to the handle assembly 14 and powered up whena shaft assembly is installed to the handle assembly 14.

In various circumstances, referring again to FIG. 19, the handleassembly 14 can include the magnetic field sensor 1402, for example,which can be configured to detect a detectable element, such as amagnetic element 1407 (FIG. 3), for example, on a shaft assembly, suchas shaft assembly 200, for example, when the shaft assembly is coupledto the handle assembly 14. The magnetic field sensor 1402 can be poweredby a power source 1406, such as a battery, for example, which can, ineffect, amplify the detection signal of the magnetic field sensor 1402and communicate with an input channel of the microcontroller 1500 viathe circuit illustrated in FIG. 19. Once the microcontroller 1500 has areceived an input indicating that a shaft assembly has been at leastpartially coupled to the handle assembly 14, and that, as a result, theelectrical contacts 1401 a-1401 f are no longer exposed, themicrocontroller 1500 can enter into its normal, or powered-up, operatingstate. In such an operating state, the microcontroller 1500 willevaluate the signals transmitted to one or more of the contacts 1401b-1401 e from the shaft assembly and/or transmit signals to the shaftassembly through one or more of the contacts 1401 b-1401 e in normal usethereof. In various circumstances, the shaft assembly 200 may have to befully seated before the magnetic field sensor 1402 can detect themagnetic element 1407. While a magnetic field sensor 1402 can beutilized to detect the presence of the shaft assembly 200, any suitablesystem of sensors and/or switches can be utilized to detect whether ashaft assembly has been assembled to the handle assembly 14, forexample. In this way, further to the above, both the power circuits andthe signal circuits to the connector 1400 can be powered down when ashaft assembly is not installed to the handle assembly 14 and powered upwhen a shaft assembly is installed to the handle assembly 14.

In various examples, as may be used throughout the present disclosure,any suitable magnetic field sensor may be employed to detect whether ashaft assembly has been assembled to the handle assembly 14, forexample. For example, the technologies used for magnetic field sensinginclude Hall effect sensor, search coil, fluxgate, optically pumped,nuclear precession, SQUID, Hall-effect, anisotropic magnetoresistance,giant magnetoresistance, magnetic tunnel junctions, giantmagnetoimpedance, magnetostrictive/piezoelectric composites,magnetodiode, magnetotransistor, fiber optic, magnetooptic, andmicroelectromechanical systems-based magnetic sensors, among others.

Referring to FIG. 19, the microcontroller 1500 may generally comprise amicroprocessor (“processor”) and one or more memory units operationallycoupled to the processor. By executing instruction code stored in thememory, the processor may control various components of the surgicalinstrument, such as the motor, various drive systems, and/or a userdisplay, for example. The microcontroller 1500 may be implemented usingintegrated and/or discrete hardware elements, software elements, and/ora combination of both. Examples of integrated hardware elements mayinclude processors, microprocessors, microcontrollers, integratedcircuits, application specific integrated circuits (ASIC), programmablelogic devices (PLD), digital signal processors (DSP), field programmablegate arrays (FPGA), logic gates, registers, semiconductor devices,chips, microchips, chip sets, microcontrollers, system-on-chip (SoC),and/or system-in-package (SIP). Examples of discrete hardware elementsmay include circuits and/or circuit elements such as logic gates, fieldeffect transistors, bipolar transistors, resistors, capacitors,inductors, and/or relays. In certain instances, the microcontroller 1500may include a hybrid circuit comprising discrete and integrated circuitelements or components on one or more substrates, for example.

Referring to FIG. 19, the microcontroller 1500 may be an LM 4F230H5QR,available from Texas Instruments, for example. In certain instances, theTexas Instruments LM4F230H5QR is an ARM Cortex-M4F Processor Corecomprising on-chip memory of 256 KB single-cycle flash memory, or othernon-volatile memory, up to 40 MHz, a prefetch buffer to improveperformance above 40 MHz, a 32 KB single-cycle serial random accessmemory (SRAM), internal read-only memory (ROM) loaded withStellarisWare® software, 2 KB electrically erasable programmableread-only memory (EEPROM), one or more pulse width modulation (PWM)modules, one or more quadrature encoder inputs (QEI) analog, one or more12-bit Analog-to-Digital Converters (ADC) with 12 analog input channels,among other features that are readily available. Other microcontrollersmay be readily substituted for use with the present disclosure.Accordingly, the present disclosure should not be limited in thiscontext.

As discussed above, the handle assembly 14 and/or the shaft assembly 200can include systems and configurations configured to prevent, or atleast reduce the possibility of, the contacts of the handle electricalconnector 1400 and/or the contacts of the shaft electrical connector1410 from becoming shorted out when the shaft assembly 200 is notassembled, or completely assembled, to the handle assembly 14. Referringto FIG. 3, the handle electrical connector 1400 can be at leastpartially recessed within a cavity 1409 defined in the handle frame 20.The six contacts 1401 a-1401 f of the electrical connector 1400 can becompletely recessed within the cavity 1409. Such arrangements can reducethe possibility of an object accidentally contacting one or more of thecontacts 1401 a-1401 f. Similarly, the shaft electrical connector 1410can be positioned within a recess defined in the shaft chassis 240 whichcan reduce the possibility of an object accidentally contacting one ormore of the contacts 1411 a-1411 f of the shaft electrical connector1410. With regard to the particular example depicted in FIG. 3, theshaft contacts 1411 a-1411 f can comprise male contacts. In at least oneexample, each shaft contact 1411 a-1411 f can comprise a flexibleprojection extending therefrom which can be configured to engage acorresponding handle contact 1401 a-1401 f, for example. The handlecontacts 1401 a-1401 f can comprise female contacts. In at least oneexample, each handle contact 1401 a-1401 f can comprise a flat surface,for example, against which the male shaft contacts 1401 a-1401 f canwipe, or slide, against and maintain an electrically conductiveinterface therebetween. In various instances, the direction in which theshaft assembly 200 is assembled to the handle assembly 14 can beparallel to, or at least substantially parallel to, the handle contacts1401 a-1401 f such that the shaft contacts 1411 a-1411 f slide againstthe handle contacts 1401 a-1401 f when the shaft assembly 200 isassembled to the handle assembly 14. In various alternative examples,the handle contacts 1401 a-1401 f can comprise male contacts and theshaft contacts 1411 a-1411 f can comprise female contacts. In certainalternative examples, the handle contacts 1401 a-1401 f and the shaftcontacts 1411 a-1411 f can comprise any suitable arrangement ofcontacts.

In various instances, the handle assembly 14 can comprise a connectorguard configured to at least partially cover the handle electricalconnector 1400 and/or a connector guard configured to at least partiallycover the shaft electrical connector 1410. A connector guard canprevent, or at least reduce the possibility of, an object accidentallytouching the contacts of an electrical connector when the shaft assemblyis not assembled to, or only partially assembled to, the handle. Aconnector guard can be movable. For instance, the connector guard can bemoved between a guarded position in which it at least partially guards aconnector and an unguarded position in which it does not guard, or atleast guards less of, the connector. In at least one example, aconnector guard can be displaced as the shaft assembly is beingassembled to the handle. For instance, if the handle comprises a handleconnector guard, the shaft assembly can contact and displace the handleconnector guard as the shaft assembly is being assembled to the handle.Similarly, if the shaft assembly comprises a shaft connector guard, thehandle can contact and displace the shaft connector guard as the shaftassembly is being assembled to the handle. In various instances, aconnector guard can comprise a door, for example. In at least oneinstance, the door can comprise a beveled surface which, when contactedby the handle or shaft, can facilitate the displacement of the door in acertain direction. In various instances, the connector guard can betranslated and/or rotated, for example. In certain instances, aconnector guard can comprise at least one film which covers the contactsof an electrical connector. When the shaft assembly is assembled to thehandle, the film can become ruptured. In at least one instance, the malecontacts of a connector can penetrate the film before engaging thecorresponding contacts positioned underneath the film.

As described above, the surgical instrument can include a system whichcan selectively power-up, or activate, the contacts of an electricalconnector, such as the electrical connector 1400, for example. Invarious instances, the contacts can be transitioned between anunactivated condition and an activated condition. In certain instances,the contacts can be transitioned between a monitored condition, adeactivated condition, and an activated condition. For instance, themicrocontroller 1500, for example, can monitor the contacts 1401 a-1401f when a shaft assembly has not been assembled to the handle assembly 14to determine whether one or more of the contacts 1401 a-1401 f may havebeen shorted. The microcontroller 1500 can be configured to apply a lowvoltage potential to each of the contacts 1401 a-1401 f and assesswhether only a minimal resistance is present at each of the contacts.Such an operating state can comprise the monitored condition. In theevent that the resistance detected at a contact is high, or above athreshold resistance, the microcontroller 1500 can deactivate thatcontact, more than one contact, or, alternatively, all of the contacts.Such an operating state can comprise the deactivated condition. If ashaft assembly is assembled to the handle assembly 14 and it is detectedby the microcontroller 1500, as discussed above, the microcontroller1500 can increase the voltage potential to the contacts 1401 a-1401 f.Such an operating state can comprise the activated condition.

The various shaft assemblies disclosed herein may employ sensors andvarious other components that require electrical communication with thecontroller in the housing. These shaft assemblies generally areconfigured to be able to rotate relative to the housing necessitating aconnection that facilitates such electrical communication between two ormore components that may rotate relative to each other. When employingend effectors of the types disclosed herein, the connector arrangementsmust be relatively robust in nature while also being somewhat compact tofit into the shaft assembly connector portion.

Referring to FIG. 20, a non-limiting form of the end effector 300 isillustrated. As described above, the end effector 300 may include theanvil 306 and the staple cartridge 304. In this non-limiting example,the anvil 306 is coupled to an elongate channel 198. For example,apertures 199 can be defined in the elongate channel 198 which canreceive pins 152 extending from the anvil 306 and allow the anvil 306 topivot from an open position to a closed position relative to theelongate channel 198 and staple cartridge 304. In addition, FIG. 20shows a firing bar 172, configured to longitudinally translate into theend effector 300. The firing bar 172 may be constructed from one solidsection, or in various examples, may include a laminate materialcomprising, for example, a stack of steel plates. A distally projectingend of the firing bar 172 can be attached to an E-beam 178 that can,among other things, assist in spacing the anvil 306 from a staplecartridge 304 positioned in the elongate channel 198 when the anvil 306is in a closed position. The E-beam 178 can also include a sharpenedcutting edge 182 which can be used to sever tissue as the E-beam 178 isadvanced distally by the firing bar 172. In operation, the E-beam 178can also actuate, or fire, the staple cartridge 304. The staplecartridge 304 can include a molded cartridge body 194 that holds aplurality of staples 191 resting upon staple drivers 192 withinrespective upwardly open staple cavities 195. A wedge sled 190 is drivendistally by the E-beam 178, sliding upon a cartridge tray 196 that holdstogether the various components of the replaceable staple cartridge 304.The wedge sled 190 upwardly cams the staple drivers 192 to force out thestaples 191 into deforming contact with the anvil 306 while a cuttingsurface 182 of the E-beam 178 severs clamped tissue.

Further to the above, the E-beam 178 can include upper pins 180 whichengage the anvil 306 during firing. The E-beam 178 can further includemiddle pins 184 and a bottom foot 186 which can engage various portionsof the cartridge body 194, cartridge tray 196 and elongate channel 198.When a staple cartridge 304 is positioned within the elongate channel198, a slot 193 defined in the cartridge body 194 can be aligned with aslot 197 defined in the cartridge tray 196 and a slot 189 defined in theelongate channel 198. In use, the E-beam 178 can slide through thealigned slots 193, 197, and 189 wherein, as indicated in FIG. 20, thebottom foot 186 of the E-beam 178 can engage a groove running along thebottom surface of channel 198 along the length of slot 189, the middlepins 184 can engage the top surfaces of cartridge tray 196 along thelength of longitudinal slot 197, and the upper pins 180 can engage theanvil 306. In such circumstances, the E-beam 178 can space, or limit therelative movement between, the anvil 306 and the staple cartridge 304 asthe firing bar 172 is moved distally to fire the staples from the staplecartridge 304 and/or incise the tissue captured between the anvil 306and the staple cartridge 304. Thereafter, the firing bar 172 and theE-beam 178 can be retracted proximally allowing the anvil 306 to beopened to release the two stapled and severed tissue portions (notshown).

Having described a surgical instrument 10 (FIGS. 1-4) in general terms,the description now turns to a detailed description of variouselectrical/electronic components of the surgical instrument 10. Turningnow to FIGS. 21A-21B, where one example of a segmented circuit 2000comprising a plurality of circuit segments 2002 a-2002 g is illustrated.The segmented circuit 2000 comprising the plurality of circuit segments2002 a-2002 g is configured to control a powered surgical instrument,such as, for example, the surgical instrument 10 illustrated in FIGS.1-18A, without limitation. The plurality of circuit segments 2002 a-2002g is configured to control one or more operations of the poweredsurgical instrument 10. A safety processor segment 2002 a (Segment 1)comprises a safety processor 2004. A primary processor segment 2002 b(Segment 2) comprises a primary or main processor 2006. The safetyprocessor 2004 and/or the primary processor 2006 are configured tointeract with one or more additional circuit segments 2002 c-2002 g tocontrol operation of the powered surgical instrument 10. The primaryprocessor 2006 comprises a plurality of inputs coupled to, for example,one or more circuit segments 2002 c-2002 g, a battery 2008, and/or aplurality of switches 2056-2070. The segmented circuit 2000 may beimplemented by any suitable circuit, such as, for example, a printedcircuit board assembly (PCBA) within the powered surgical instrument 10.It should be understood that the term processor as used herein includesany microprocessor, microcontroller, or other basic computing devicethat incorporates the functions of a computer's central processing unit(CPU) on an integrated circuit or at most a few integrated circuits. Theprocessor is a multipurpose, programmable device that accepts digitaldata as input, processes it according to instructions stored in itsmemory, and provides results as output. It is an example of sequentialdigital logic, as it has internal memory. Processors operate on numbersand symbols represented in the binary numeral system.

In one aspect, the main processor 2006 may be any single core ormulticore processor such as those known under the trade name ARM Cortexby Texas Instruments. In one example, the safety processor 2004 may be asafety microcontroller platform comprising two microcontroller-basedfamilies such as TMS570 and RM4x known under the trade name Hercules ARMCortex R4, also by Texas Instruments. Nevertheless, other suitablesubstitutes for microcontrollers and safety processor may be employed,without limitation. In one example, the safety processor 2004 may beconfigured specifically for IEC 61508 and ISO 26262 safety criticalapplications, among others, to provide advanced integrated safetyfeatures while delivering scalable performance, connectivity, and memoryoptions.

In certain instances, the main processor 2006 may be an LM 4F230H5QR,available from Texas Instruments, for example. In at least one example,the Texas Instruments LM4F230H5QR is an ARM Cortex-M4F Processor Corecomprising on-chip memory of 256 KB single-cycle flash memory, or othernon-volatile memory, up to 40 MHz, a prefetch buffer to improveperformance above 40 MHz, a 32 KB single-cycle SRAM, internal ROM loadedwith StellarisWare® software, 2 KB EEPROM, one or more PWM modules, oneor more QEI analog, one or more 12-bit ADC with 12 analog inputchannels, among other features that are readily available for theproduct datasheet. Other processors may be readily substituted and,accordingly, the present disclosure should not be limited in thiscontext.

In one aspect, the segmented circuit 2000 comprises an accelerationsegment 2002 c (Segment 3). The acceleration segment 2002 c comprises anacceleration sensor 2022. The acceleration sensor 2022 may comprise, forexample, an accelerometer. The acceleration sensor 2022 is configured todetect movement or acceleration of the powered surgical instrument 10.In some examples, input from the acceleration sensor 2022 is used, forexample, to transition to and from a sleep mode, identify an orientationof the powered surgical instrument, and/or identify when the surgicalinstrument has been dropped. In some examples, the acceleration segment2002 c is coupled to the safety processor 2004 and/or the primaryprocessor 2006.

In some aspects, the segmented circuit 2000 comprises a display segment2002 d (Segment 4). According to various embodiments, the displaysegment 2002 d comprises a display connector (not shown) which iscoupled to the primary processor 2006, one or more display driverintegrated circuits (not shown) which are coupled to the displayconnector, and a display 2028 which is coupled to the one or moredisplay driver integrated circuits. The display connector and the one ormore display driver integrated circuits are shown, for example, in FIG.4B of U.S. patent application Ser. No. 14/226,076, the content of whichis hereby incorporated by reference in its entirety. The display driverintegrated circuits may be integrated with the display 2028 and/or maybe located separately from the display 2028. The display 2028 maycomprise any suitable display, such as, for example, an organiclight-emitting diode (OLED) display, a liquid-crystal display (LCD),and/or any other suitable display. In some examples, the display segment2002 d is coupled to the safety processor 2004.

In some aspects, the segmented circuit 2000 comprises a shaft segment2002 e (Segment 5). The shaft segment 2002 e comprises one or morecontrols for a shaft assembly (e.g., shaft assembly 200) coupled to thesurgical instrument 10 and/or one or more controls for an end effector(e.g., end effector 300) coupled to the shaft 200. According to variousembodiments, the shaft segment 2002 e comprises a shaft connector 2030and a shaft printed circuit board assembly (PCBA) 2031. The shaftconnector 2030 is configured to couple the shaft PCBA 2031 to theprimary processor 2006. According to various embodiments, the shaft PCBA2031 comprises a first articulation switch (not shown), a secondarticulation switch (not shown), and a shaft PCBA EEPROM (not shown). Insome examples, the shaft PCBA EEPROM comprises one or more parameters,routines, and/or programs specific to the shaft assembly 200 and/or theshaft PCBA 2031. The shaft PCBA 2031 may be coupled to the shaftassembly 200 and/or integral with the surgical instrument 10. In someexamples, the shaft segment 2002 e comprises a second shaft EEPROM (notshown). The second shaft EEPROM comprises a plurality of algorithms,routines, parameters, and/or other data corresponding to one or moreshaft assemblies 200 and/or end effectors 300 which may be interfacedwith the powered surgical instrument 10. The first articulation switch,the second articulation switch, and the shaft PCBA EEPROMs are shown,for example, in FIG. 4A of U.S. patent application Ser. No. 14/226,076,the content of which is hereby incorporated by reference in itsentirety. According to other embodiments, as shown in FIG. 21A, theshaft segment 2002 e comprises the shaft PCBA 2031, a Hall effect sensor2070 and the shaft connector 2025. The shaft PCBA 2031 comprises alow-power microprocessor 2090 with ferroelectric random access memory(FRAM) technology, a mechanical articulation switch 2092, a shaftrelease Hall effect switch 2094 and flash memory 2034. The Hall effectsensor 2070 is utilized to indicate engagement of the shaft assembly 200and thus may be considered a shaft engaged switch.

In some aspects, the segmented circuit 2000 comprises a position encodersegment 2002 f (Segment 6). The position encoder segment 2002 fcomprises one or more magnetic rotary position encoders 2040 a-2040 b.The one or more magnetic rotary position encoders 2040 a-2040 b areconfigured to identify the rotational position of a motor 2048, a shaftassembly 200, and/or an end effector 300 of the surgical instrument 10.In some examples, the magnetic rotary position encoders 2040 a-2040 bmay be coupled to the safety processor 2004 and/or the primary processor2006.

In some aspects, the segmented circuit 2000 comprises a motor segment2002 g (Segment 7). The motor segment 2002 g comprises a motor 2048,such as, for example, a brushed DC motor, configured to control one ormore movements of the powered surgical instrument 10. The motor 2048 iscoupled to the primary processor 2006 through a motor controller 2043, aplurality of H-bridge drivers 2042 and a plurality of H-bridgefield-effect transistors (not shown). According to various embodiments,the H-bridge field-effect transistors (FETs) are coupled to the safetyprocessor 2004. The H-bridge FETs are shown, for example, in FIG. 4B ofU.S. patent application Ser. No. 14/226,076, the content of which ishereby incorporated by reference in its entirety. The motor controller2043 controls a first motor flag 2074 a and a second motor flag 2074 bto indicate the status and position of the motor 2048 to the primaryprocessor 2006. The primary processor 2006 provides a pulse-widthmodulation (PWM) high signal 2076 a, a PWM low signal 2076 b, adirection signal 2078, a synchronize signal 2080, and a motor resetsignal 2082 to the motor controller 2043 through a buffer 2084. A motorcurrent sensor 2046 is coupled in series with the motor 2048 to measurethe current draw of the motor 2048. The motor current sensor 2046 is insignal communication with the primary processor 2006 and/or the safetyprocessor 2004. In some examples, the motor 2048 is coupled to a motorelectromagnetic interference (EMI) filter (not shown). The EMI filter isshown, for example, in FIG. 3B of U.S. patent application Ser. No.14/226,076, the content of which is hereby incorporated by reference inits entirety.

In some aspects, the segmented circuit 2000 comprises a power segment2002 h (Segment 8) configured to provide a segment voltage to each ofthe circuit segments 1102 a-1102 g. A battery 2008 is coupled to thesafety processor 2004, the primary processor 2006, and one or more ofthe additional circuit segments 2002 c-2002 g. The battery 2008 iscoupled to the segmented circuit 2000 by a battery connector 2010 and acurrent sensor 2012. The current sensor 2012 is configured to measurethe total current draw of the segmented circuit 2000. In some examples,one or more voltage converters 2014 a, 2014 b, 2016 are configured toprovide predetermined voltage values to one or more circuit segments2002 a-2002 g. For example, in some examples, the segmented circuit 2000may comprise 3.3V voltage converters 2014 a-2014 b and/or 5V voltageconverters 2016. A boost converter 2018 is configured to provide a boostvoltage up to a predetermined amount, such as, for example, up to 13V.The boost converter 2018 is configured to provide additional voltageand/or current during power intensive operations and prevent brownout orlow-power conditions. A transistor switch (e.g., N-Channel MOSFET) 2015is coupled to the power converters 2014B, 2016.

In some aspects, the safety segment 2002 a comprises a motor powerinterrupt 2020. The motor power interrupt 2020 is coupled between thepower segment 2002 h and the motor segment 2002 g. A transistor switch(e.g., N-Channel MOSFET) 2057 is coupled to the motor power interrupt2020. The safety segment 2002 a is configured to interrupt power to themotor segment 2002 g when an error or fault condition is detected by thesafety processor 2004 and/or the primary processor 2006 as discussed inmore detail herein. Although the circuit segments 2002 a-2002 g areillustrated with all components of the circuit segments 2002 a-2002 hlocated in physical proximity, one skilled in the art will recognizethat a circuit segment 2002 a-2002 h may comprise components physicallyand/or electrically separate from other components of the same circuitsegment 2002 a-2002 g. In some examples, one or more components may beshared between two or more circuit segments 2002 a-2002 g.

In some aspects, a plurality of switches 2056-2070 are coupled to thesafety processor 2004 and/or the primary processor 2006. The pluralityof switches 2056-2070 may be configured to control one or moreoperations of the surgical instrument 10, control one or more operationsof the segmented circuit 2000, and/or indicate a status of the surgicalinstrument 10. For example, a bail-out door switch 2056 is configured toindicate the status of a bail-out door. A plurality of articulationswitches, such as, for example, a left side articulation left switch2058 a, a left side articulation right switch 2060 a, a left sidearticulation center switch 2062 a, a right side articulation left switch2058 b, a right side articulation right switch 2060 b, and a right sidearticulation center switch 2062 b are configured to control articulationof a shaft assembly 200 and/or an end effector 300. A left side reverseswitch 2064 a and a right side reverse switch 2064 b are coupled to theprimary processor 2006. In some examples, the left side switchescomprising the left side articulation left switch 2058 a, the left sidearticulation right switch 2060 a, the left side articulation centerswitch 2062 a, and the left side reverse switch 2064 a are coupled tothe primary processor 2006 by a left flex connector (not shown). Theright side switches comprising the right side articulation left switch2058 b, the right side articulation right switch 2060 b, the right sidearticulation center switch 2062 b, and the right side reverse switch2064 b are coupled to the primary processor 2006 by a right flexconnector (not shown). The left flex connector and the right flexconnector are shown, for example, in FIG. 3A of U.S. patent applicationSer. No. 14/226,076, the content of which is hereby incorporated byreference in its entirety. In some examples, a firing switch 2066, aclamp release switch 2068, and the Hall effect sensor/shaft engagedswitch 2070 are coupled to the primary processor 2006.

In some aspects, the plurality of switches 2056-2070 may comprise, forexample, a plurality of handle controls mounted to a handle of thesurgical instrument 10, a plurality of indicator switches, and/or anycombination thereof. In various examples, the plurality of switches2056-2070 allow a surgeon to manipulate the surgical instrument, providefeedback to the segmented circuit 2000 regarding the position and/oroperation of the surgical instrument, and/or indicate unsafe operationof the surgical instrument 10. In some examples, additional or fewerswitches may be coupled to the segmented circuit 2000, one or more ofthe switches 2056-2070 may be combined into a single switch, and/orexpanded to multiple switches. For example, in one example, one or moreof the left side and/or right side articulation switches 2058 a-2064 bmay be combined into a single multi-position switch.

In one aspect, the safety processor 2004 is configured to implement awatchdog function, among other safety operations. The safety processor2004 and the primary processor 2006 of the segmented circuit 2000 are insignal communication. The primary processor 2006 is also coupled to aflash memory 2086. A microprocessor alive heartbeat signal is providedat output 2096. The acceleration segment 2002 c comprises anaccelerometer 2022 configured to monitor movement of the surgicalinstrument 10. In various examples, the accelerometer 2022 may be asingle, double, or triple axis accelerometer. The accelerometer 2022 maybe employed to measure proper acceleration that is not necessarily thecoordinate acceleration (rate of change of velocity). Instead, theaccelerometer sees the acceleration associated with the phenomenon ofweight experienced by a test mass at rest in the frame of reference ofthe accelerometer 2022. For example, the accelerometer 2022 at rest onthe surface of the earth will measure an acceleration g=9.8 m/s²(gravity) straight upwards, due to its weight. Another type ofacceleration that accelerometer 2022 can measure is g-forceacceleration. In various other examples, the accelerometer 2022 maycomprise a single, double, or triple axis accelerometer. Further, theacceleration segment 2002 c may comprise one or more inertial sensors todetect and measure acceleration, tilt, shock, vibration, rotation, andmultiple degrees-of-freedom (DoF). A suitable inertial sensor maycomprise an accelerometer (single, double, or triple axis), amagnetometer to measure a magnetic field in space such as the earth'smagnetic field, and/or a gyroscope to measure angular velocity.

In one aspect, the safety processor 2004 is configured to implement awatchdog function with respect to one or more circuit segments 2002c-2002 h, such as, for example, the motor segment 2002 g. In thisregards, the safety processor 2004 employs the watchdog function todetect and recover from malfunctions of the primary processor 2006.During normal operation, the safety processor 2004 monitors for hardwarefaults or program errors of the primary processor 2006 and to initiatecorrective action or actions. The corrective actions may include placingthe primary processor 2006 in a safe state and restoring normal systemoperation. In one example, the safety processor 2004 is coupled to atleast a first sensor. The first sensor measures a first property of thesurgical instrument 10 (FIGS. 1-4). In some examples, the safetyprocessor 2004 is configured to compare the measured property of thesurgical instrument 10 to a predetermined value. For example, in oneexample, a motor sensor 2040 a (e.g., a magnetic rotary positionencoder) is coupled to the safety processor 2004. The motor sensor 2040a provides motor speed and position information to the safety processor2004. The safety processor 2004 monitors the motor sensor 2040 a andcompares the value to a maximum speed and/or position value and preventsoperation of the motor 2048 above the predetermined values. In someexamples, the predetermined values are calculated based on real-timespeed and/or position of the motor 2048, calculated from values suppliedby a second motor sensor 2040 b (e.g., a magnetic rotary positionencoder) in communication with the primary processor 2006, and/orprovided to the safety processor 2004 from, for example, a memory modulecoupled to the safety processor 2004.

In some aspects, a second sensor is coupled to the primary processor2006. The second sensor is configured to measure the first physicalproperty. The safety processor 2004 and the primary processor 2006 areconfigured to provide a signal indicative of the value of the firstsensor and the second sensor respectively. When either the safetyprocessor 2004 or the primary processor 2006 indicates a value outsideof an acceptable range, the segmented circuit 2000 prevents operation ofat least one of the circuit segments 2002 c-2002 h, such as, forexample, the motor segment 2002 g. For example, in the exampleillustrated in FIGS. 21A-21B, the safety processor 2004 is coupled to afirst motor position sensor 2040 a and the primary processor 2006 iscoupled to a second motor position sensor 2040 b. The motor positionsensors 2040 a, 2040 b may comprise any suitable motor position sensor,such as, for example, a magnetic angle rotary input comprising a sineand cosine output. The motor position sensors 2040 a, 2040 b providerespective signals to the safety processor 2004 and the primaryprocessor 2006 indicative of the position of the motor 2048.

The safety processor 2004 and the primary processor 2006 generate anactivation signal when the values of the first motor sensor 2040 a andthe second motor sensor 2040 b are within a predetermined range. Wheneither the primary processor 2006 or the safety processor 2004 detect avalue outside of the predetermined range, the activation signal isterminated and operation of at least one circuit segment 2002 c-2002 h,such as, for example, the motor segment 2002 g, is interrupted and/orprevented. For example, in some examples, the activation signal from theprimary processor 2006 and the activation signal from the safetyprocessor 2004 are coupled to an AND gate 2059. The AND gate 2059 iscoupled to a motor power switch 2020. The AND gate 2059 maintains themotor power switch 2020 in a closed, or on, position when the activationsignal from both the safety processor 2004 and the primary processor2006 are high, indicating a value of the motor sensors 2040 a, 2040 bwithin the predetermined range. When either of the motor sensors 2040 a,2040 b detect a value outside of the predetermined range, the activationsignal from that motor sensor 2040 a, 2040 b is set low, and the outputof the AND gate 2059 is set low, opening the motor power switch 2020. Insome examples, the value of the first sensor 2040 a and the secondsensor 2040 b is compared, for example, by the safety processor 2004and/or the primary processor 2006. When the values of the first sensorand the second sensor are different, the safety processor 2004 and/orthe primary processor 2006 may prevent operation of the motor segment2002 g.

In some aspects, the safety processor 2004 receives a signal indicativeof the value of the second sensor 2040 b and compares the second sensorvalue to the first sensor value. For example, in one aspect, the safetyprocessor 2004 is coupled directly to a first motor sensor 2040 a. Asecond motor sensor 2040 b is coupled to a primary processor 2006, whichprovides the second motor sensor 2040 b value to the safety processor2004, and/or coupled directly to the safety processor 2004. The safetyprocessor 2004 compares the value of the first motor sensor 2040 to thevalue of the second motor sensor 2040 b. When the safety processor 2004detects a mismatch between the first motor sensor 2040 a and the secondmotor sensor 2040 b, the safety processor 2004 may interrupt operationof the motor segment 2002 g, for example, by cutting power to the motorsegment 2002 g.

In some aspects, the safety processor 2004 and/or the primary processor2006 is coupled to a first sensor 2040 a configured to measure a firstproperty of a surgical instrument and a second sensor 2040 b configuredto measure a second property of the surgical instrument. The firstproperty and the second property comprise a predetermined relationshipwhen the surgical instrument is operating normally. The safety processor2004 monitors the first property and the second property. When a valueof the first property and/or the second property inconsistent with thepredetermined relationship is detected, a fault occurs. When a faultoccurs, the safety processor 2004 takes at least one action, such as,for example, preventing operation of at least one of the circuitsegments, executing a predetermined operation, and/or resetting theprimary processor 2006. For example, the safety processor 2004 may openthe motor power switch 2020 to cut power to the motor circuit segment2002 g when a fault is detected.

In one aspect, the safety processor 2004 is configured to execute anindependent control algorithm. In operation, the safety processor 2004monitors the segmented circuit 2000 and is configured to control and/oroverride signals from other circuit components, such as, for example,the primary processor 2006, independently. The safety processor 2004 mayexecute a preprogrammed algorithm and/or may be updated or programmed onthe fly during operation based on one or more actions and/or positionsof the surgical instrument 10. For example, in one example, the safetyprocessor 2004 is reprogrammed with new parameters and/or safetyalgorithms each time a new shaft and/or end effector is coupled to thesurgical instrument 10. In some examples, one or more safety valuesstored by the safety processor 2004 are duplicated by the primaryprocessor 2006. Two-way error detection is performed to ensure valuesand/or parameters stored by either of the processors 2004, 2006 arecorrect.

In some aspects, the safety processor 2004 and the primary processor2006 implement a redundant safety check. The safety processor 2004 andthe primary processor 2006 provide periodic signals indicating normaloperation. For example, during operation, the safety processor 2004 mayindicate to the primary processor 2006 that the safety processor 2004 isexecuting code and operating normally. The primary processor 2006 may,likewise, indicate to the safety processor 2004 that the primaryprocessor 2006 is executing code and operating normally. In someexamples, communication between the safety processor 2004 and theprimary processor 2006 occurs at a predetermined interval. Thepredetermined interval may be constant or may be variable based on thecircuit state and/or operation of the surgical instrument 10.

FIG. 22 illustrates one example of a power assembly 2100 comprising ausage cycle circuit 2102 configured to monitor a usage cycle count ofthe power assembly 2100. The power assembly 2100 may be coupled to asurgical instrument 2110. The usage cycle circuit 2102 comprises aprocessor 2104 and a use indicator 2106. The use indicator 2106 isconfigured to provide a signal to the processor 2104 to indicate a useof the battery back 2100 and/or a surgical instrument 2110 coupled tothe power assembly 2100. A “use” may comprise any suitable action,condition, and/or parameter such as, for example, changing a modularcomponent of a surgical instrument 2110, deploying or firing adisposable component coupled to the surgical instrument 2110, deliveringelectrosurgical energy from the surgical instrument 2110, reconditioningthe surgical instrument 2110 and/or the power assembly 2100, exchangingthe power assembly 2100, recharging the power assembly 2100, and/orexceeding a safety limitation of the surgical instrument 2110 and/or thebattery back 2100.

In some instances, a usage cycle, or use, is defined by one or morepower assembly 2100 parameters. For example, in one instance, a usagecycle comprises using more than 5% of the total energy available fromthe power assembly 2100 when the power assembly 2100 is at a full chargelevel. In another instance, a usage cycle comprises a continuous energydrain from the power assembly 2100 exceeding a predetermined time limit.For example, a usage cycle may correspond to five minutes of continuousand/or total energy draw from the power assembly 2100. In someinstances, the power assembly 2100 comprises a usage cycle circuit 2102having a continuous power draw to maintain one or more components of theusage cycle circuit 2102, such as, for example, the use indicator 2106and/or a counter 2108, in an active state.

The processor 2104 maintains a usage cycle count. The usage cycle countindicates the number of uses detected by the use indicator 2106 for thepower assembly 2100 and/or the surgical instrument 2110. The processor2104 may increment and/or decrement the usage cycle count based on inputfrom the use indicator 2106. The usage cycle count is used to controlone or more operations of the power assembly 2100 and/or the surgicalinstrument 2110. For example, in some instances, a power assembly 2100is disabled when the usage cycle count exceeds a predetermined usagelimit. Although the instances discussed herein are discussed withrespect to incrementing the usage cycle count above a predeterminedusage limit, those skilled in the art will recognize that the usagecycle count may start at a predetermined amount and may be decrementedby the processor 2104. In this instance, the processor 2104 initiatesand/or prevents one or more operations of the power assembly 2100 whenthe usage cycle count falls below a predetermined usage limit.

The usage cycle count is maintained by a counter 2108. The counter 2108comprises any suitable circuit, such as, for example, a memory module,an analog counter, and/or any circuit configured to maintain a usagecycle count. In some instances, the counter 2108 is formed integrallywith the processor 2104. In other instances, the counter 2108 comprisesa separate component, such as, for example, a solid state memory module.In some instances, the usage cycle count is provided to a remote system,such as, for example, a central database. The usage cycle count istransmitted by a communications module 2112 to the remote system. Thecommunications module 2112 is configured to use any suitablecommunications medium, such as, for example, wired and/or wirelesscommunication. In some instances, the communications module 2112 isconfigured to receive one or more instructions from the remote system,such as, for example, a control signal when the usage cycle countexceeds the predetermined usage limit.

In some instances, the use indicator 2106 is configured to monitor thenumber of modular components used with a surgical instrument 2110coupled to the power assembly 2100. A modular component may comprise,for example, a modular shaft, a modular end effector, and/or any othermodular component. In some instances, the use indicator 2106 monitorsthe use of one or more disposable components, such as, for example,insertion and/or deployment of a staple cartridge within an end effectorcoupled to the surgical instrument 2110. The use indicator 2106comprises one or more sensors for detecting the exchange of one or moremodular and/or disposable components of the surgical instrument 2110.

In some instances, the use indicator 2106 is configured to monitorsingle patient surgical procedures performed while the power assembly2100 is installed. For example, the use indicator 2106 may be configuredto monitor firings of the surgical instrument 2110 while the powerassembly 2100 is coupled to the surgical instrument 2110. A firing maycorrespond to deployment of a staple cartridge, application ofelectrosurgical energy, and/or any other suitable surgical event. Theuse indicator 2106 may comprise one or more circuits for measuring thenumber of firings while the power assembly 2100 is installed. The useindicator 2106 provides a signal to the processor 2104 when a singlepatient procedure is performed and the processor 2104 increments theusage cycle count.

In some instances, the use indicator 2106 comprises a circuit configuredto monitor one or more parameters of the power source 2114, such as, forexample, a current draw from the power source 2114. The one or moreparameters of the power source 2114 correspond to one or more operationsperformable by the surgical instrument 2110, such as, for example, acutting and sealing operation. The use indicator 2106 provides the oneor more parameters to the processor 2104, which increments the usagecycle count when the one or more parameters indicate that a procedurehas been performed.

In some instances, the use indicator 2106 comprises a timing circuitconfigured to increment a usage cycle count after a predetermined timeperiod. The predetermined time period corresponds to a single patientprocedure time, which is the time required for an operator to perform aprocedure, such as, for example, a cutting and sealing procedure. Whenthe power assembly 2100 is coupled to the surgical instrument 2110, theprocessor 2104 polls the use indicator 2106 to determine when the singlepatient procedure time has expired. When the predetermined time periodhas elapsed, the processor 2104 increments the usage cycle count. Afterincrementing the usage cycle count, the processor 2104 resets the timingcircuit of the use indicator 2106.

In some instances, the use indicator 2106 comprises a time constant thatapproximates the single patient procedure time. In one example, theusage cycle circuit 2102 comprises a resistor-capacitor (RC) timingcircuit 2506. The RC timing circuit comprises a time constant defined bya resistor-capacitor pair. The time constant is defined by the values ofthe resistor and the capacitor. In one example, the usage cycle circuit2552 comprises a rechargeable battery and a clock. When the powerassembly 2100 is installed in a surgical instrument, the rechargeablebattery is charged by the power source. The rechargeable batterycomprises enough power to run the clock for at least the single patientprocedure time. The clock may comprise a real time clock, a processorconfigured to implement a time function, or any other suitable timingcircuit.

Referring still to FIG. 22, in some instances, the use indicator 2106comprises a sensor configured to monitor one or more environmentalconditions experienced by the power assembly 2100. For example, the useindicator 2106 may comprise an accelerometer. The accelerometer isconfigured to monitor acceleration of the power assembly 2100. The powerassembly 2100 comprises a maximum acceleration tolerance. Accelerationabove a predetermined threshold indicates, for example, that the powerassembly 2100 has been dropped. When the use indicator 2106 detectsacceleration above the maximum acceleration tolerance, the processor2104 increments a usage cycle count. In some instances, the useindicator 2106 comprises a moisture sensor. The moisture sensor isconfigured to indicate when the power assembly 2100 has been exposed tomoisture. The moisture sensor may comprise, for example, an immersionsensor configured to indicate when the power assembly 2100 has beenfully immersed in a cleaning fluid, a moisture sensor configured toindicate when moisture is in contact with the power assembly 2100 duringuse, and/or any other suitable moisture sensor.

In some instances, the use indicator 2106 comprises a chemical exposuresensor. The chemical exposure sensor is configured to indicate when thepower assembly 2100 has come into contact with harmful and/or dangerouschemicals. For example, during a sterilization procedure, aninappropriate chemical may be used that leads to degradation of thepower assembly 2100. The processor 2104 increments the usage cycle countwhen the use indicator 2106 detects an inappropriate chemical.

In some instances, the usage cycle circuit 2102 is configured to monitorthe number of reconditioning cycles experienced by the power assembly2100. A reconditioning cycle may comprise, for example, a cleaningcycle, a sterilization cycle, a charging cycle, routine and/orpreventative maintenance, and/or any other suitable reconditioningcycle. The use indicator 2106 is configured to detect a reconditioningcycle. For example, the use indicator 2106 may comprise a moisturesensor to detect a cleaning and/or sterilization cycle. In someinstances, the usage cycle circuit 2102 monitors the number ofreconditioning cycles experienced by the power assembly 2100 anddisables the power assembly 2100 after the number of reconditioningcycles exceeds a predetermined threshold.

The usage cycle circuit 2102 may be configured to monitor the number ofpower assembly 2100 exchanges. The usage cycle circuit 2102 incrementsthe usage cycle count each time the power assembly 2100 is exchanged.When the maximum number of exchanges is exceeded the usage cycle circuit2102 locks out the power assembly 2100 and/or the surgical instrument2110. In some instances, when the power assembly 2100 is coupled thesurgical instrument 2110, the usage cycle circuit 2102 identifies theserial number of the power assembly 2100 and locks the power assembly2100 such that the power assembly 2100 is usable only with the surgicalinstrument 2110. In some instances, the usage cycle circuit 2102increments the usage cycle each time the power assembly 2100 is removedfrom and/or coupled to the surgical instrument 2110.

In some instances, the usage cycle count corresponds to sterilization ofthe power assembly 2100. The use indicator 2106 comprises a sensorconfigured to detect one or more parameters of a sterilization cycle,such as, for example, a temperature parameter, a chemical parameter, amoisture parameter, and/or any other suitable parameter. The processor2104 increments the usage cycle count when a sterilization parameter isdetected. The usage cycle circuit 2102 disables the power assembly 2100after a predetermined number of sterilizations. In some instances, theusage cycle circuit 2102 is reset during a sterilization cycle, avoltage sensor to detect a recharge cycle, and/or any suitable sensor.The processor 2104 increments the usage cycle count when areconditioning cycle is detected. The usage cycle circuit 2102 isdisabled when a sterilization cycle is detected. The usage cycle circuit2102 is reactivated and/or reset when the power assembly 2100 is coupledto the surgical instrument 2110. In some instances, the use indicatorcomprises a zero power indicator. The zero power indicator changes stateduring a sterilization cycle and is checked by the processor 2104 whenthe power assembly 2100 is coupled to a surgical instrument 2110. Whenthe zero power indicator indicates that a sterilization cycle hasoccurred, the processor 2104 increments the usage cycle count.

A counter 2108 maintains the usage cycle count. In some instances, thecounter 2108 comprises a non-volatile memory module. The processor 2104increments the usage cycle count stored in the non-volatile memorymodule each time a usage cycle is detected. The memory module may beaccessed by the processor 2104 and/or a control circuit, such as, forexample, the control circuit 2000. When the usage cycle count exceeds apredetermined threshold, the processor 2104 disables the power assembly2100. In some instances, the usage cycle count is maintained by aplurality of circuit components. For example, in one instance, thecounter 2108 comprises a resistor (or fuse) pack. After each use of thepower assembly 2100, a resistor (or fuse) is burned to an open position,changing the resistance of the resistor pack. The power assembly 2100and/or the surgical instrument 2110 reads the remaining resistance. Whenthe last resistor of the resistor pack is burned out, the resistor packhas a predetermined resistance, such as, for example, an infiniteresistance corresponding to an open circuit, which indicates that thepower assembly 2100 has reached its usage limit. In some instances, theresistance of the resistor pack is used to derive the number of usesremaining.

In some instances, the usage cycle circuit 2102 prevents further use ofthe power assembly 2100 and/or the surgical instrument 2110 when theusage cycle count exceeds a predetermined usage limit. In one instance,the usage cycle count associated with the power assembly 2100 isprovided to an operator, for example, utilizing a screen formedintegrally with the surgical instrument 2110. The surgical instrument2110 provides an indication to the operator that the usage cycle counthas exceeded a predetermined limit for the power assembly 2100, andprevents further operation of the surgical instrument 2110.

In some instances, the usage cycle circuit 2102 is configured tophysically prevent operation when the predetermined usage limit isreached. For example, the power assembly 2100 may comprise a shieldconfigured to deploy over contacts of the power assembly 2100 when theusage cycle count exceeds the predetermined usage limit. The shieldprevents recharge and use of the power assembly 2100 by covering theelectrical connections of the power assembly 2100.

In some instances, the usage cycle circuit 2102 is located at leastpartially within the surgical instrument 2110 and is configured tomaintain a usage cycle count for the surgical instrument 2110. FIG. 22illustrates one or more components of the usage cycle circuit 2102within the surgical instrument 2110 in phantom, illustrating thealternative positioning of the usage cycle circuit 2102. When apredetermined usage limit of the surgical instrument 2110 is exceeded,the usage cycle circuit 2102 disables and/or prevents operation of thesurgical instrument 2110. The usage cycle count is incremented by theusage cycle circuit 2102 when the use indicator 2106 detects a specificevent and/or requirement, such as, for example, firing of the surgicalinstrument 2110, a predetermined time period corresponding to a singlepatient procedure time, based on one or more motor parameters of thesurgical instrument 2110, in response to a system diagnostic indicatingthat one or more predetermined thresholds are met, and/or any othersuitable requirement. As discussed above, in some instances, the useindicator 2106 comprises a timing circuit corresponding to a singlepatient procedure time. In other instances, the use indicator 2106comprises one or more sensors configured to detect a specific eventand/or condition of the surgical instrument 2110.

In some instances, the usage cycle circuit 2102 is configured to preventoperation of the surgical instrument 2110 after the predetermined usagelimit is reached. In some instances, the surgical instrument 2110comprises a visible indicator to indicate when the predetermined usagelimit has been reached and/or exceeded. For example, a flag, such as ared flag, may pop-up from the surgical instrument 2110, such as from thehandle, to provide a visual indication to the operator that the surgicalinstrument 2110 has exceeded the predetermined usage limit. As anotherexample, the usage cycle circuit 2102 may be coupled to a display formedintegrally with the surgical instrument 2110. The usage cycle circuit2102 displays a message indicating that the predetermined usage limithas been exceeded. The surgical instrument 2110 may provide an audibleindication to the operator that the predetermined usage limit has beenexceeded. For example, in one instance, the surgical instrument 2110emits an audible tone when the predetermined usage limit is exceeded andthe power assembly 2100 is removed from the surgical instrument 2110.The audible tone indicates the last use of the surgical instrument 2110and indicates that the surgical instrument 2110 should be disposed orreconditioned.

In some instances, the usage cycle circuit 2102 is configured totransmit the usage cycle count of the surgical instrument 2110 to aremote location, such as, for example, a central database. The usagecycle circuit 2102 comprises a communications module 2112 configured totransmit the usage cycle count to the remote location. Thecommunications module 2112 may utilize any suitable communicationssystem, such as, for example, wired or wireless communications system.The remote location may comprise a central database configured tomaintain usage information. In some instances, when the power assembly2100 is coupled to the surgical instrument 2110, the power assembly 2100records a serial number of the surgical instrument 2110. The serialnumber is transmitted to the central database, for example, when thepower assembly 2100 is coupled to a charger. In some instances, thecentral database maintains a count corresponding to each use of thesurgical instrument 2110. For example, a bar code associated with thesurgical instrument 2110 may be scanned each time the surgicalinstrument 2110 is used. When the use count exceeds a predeterminedusage limit, the central database provides a signal to the surgicalinstrument 2110 indicating that the surgical instrument 2110 should bediscarded.

The surgical instrument 2110 may be configured to lock and/or preventoperation of the surgical instrument 2110 when the usage cycle countexceeds a predetermined usage limit. In some instances, the surgicalinstrument 2110 comprises a disposable instrument and is discarded afterthe usage cycle count exceeds the predetermined usage limit. In otherinstances, the surgical instrument 2110 comprises a reusable surgicalinstrument which may be reconditioned after the usage cycle countexceeds the predetermined usage limit. The surgical instrument 2110initiates a reversible lockout after the predetermined usage limit ismet. A technician reconditions the surgical instrument 2110 and releasesthe lockout, for example, utilizing a specialized technician keyconfigured to reset the usage cycle circuit 2102.

In some aspects, the segmented circuit 2000 is configured for sequentialstart-up. An error check is performed by each circuit segment 2002a-2002 g prior to energizing the next sequential circuit segment 2002a-2002 g. FIG. 23 illustrates one example of a process for sequentiallyenergizing a segmented circuit 2270, such as, for example, the segmentedcircuit 2000. When a battery 2008 is coupled to the segmented circuit2000, the safety processor 2004 is energized 2272. The safety processor2004 performs a self-error check 2274. When an error is detected 2276 a,the safety processor stops energizing the segmented circuit 2000 andgenerates an error code 2278 a. When no errors are detected 2276 b, thesafety processor 2004 initiates 2278 b power-up of the primary processor2006. The primary processor 2006 performs a self-error check. When noerrors are detected, the primary processor 2006 begins sequentialpower-up of each of the remaining circuit segments 2278 b. Each circuitsegment is energized and error checked by the primary processor 2006.When no errors are detected, the next circuit segment is energized 2278b. When an error is detected, the safety processor 2004 and/or theprimary process stops energizing the current segment and generates anerror 2278 a. The sequential start-up continues until all of the circuitsegments 2002 a-2002 g have been energized.

FIG. 24 illustrates one aspect of a power segment 2302 comprising aplurality of daisy chained power converters 2314, 2316, 2318. The powersegment 2302 comprises a battery 2308. The battery 2308 is configured toprovide a source voltage, such as, for example, 12V. A current sensor2312 is coupled to the battery 2308 to monitor the current draw of asegmented circuit and/or one or more circuit segments. The currentsensor 2312 is coupled to an FET switch 2313. The battery 2308 iscoupled to one or more voltage converters 2309, 2314, 2316. An always onconverter 2309 provides a constant voltage to one or more circuitcomponents, such as, for example, a motion sensor 2322. The always onconverter 2309 comprises, for example, a 3.3V converter. The always onconverter 2309 may provide a constant voltage to additional circuitcomponents, such as, for example, a safety processor (not shown). Thebattery 2308 is coupled to a boost converter 2318. The boost converter2318 is configured to provide a boosted voltage above the voltageprovided by the battery 2308. For example, in the illustrated example,the battery 2308 provides a voltage of 12V. The boost converter 2318 isconfigured to boost the voltage to 13V. The boost converter 2318 isconfigured to maintain a minimum voltage during operation of a surgicalinstrument, for example, the surgical instrument 10 (FIGS. 1-4).Operation of a motor can result in the power provided to the primaryprocessor 2306 dropping below a minimum threshold and creating abrownout or reset condition in the primary processor 2306. The boostconverter 2318 ensures that sufficient power is available to the primaryprocessor 2306 and/or other circuit components, such as the motorcontroller 2343, during operation of the surgical instrument 10. In someexamples, the boost converter 2318 is coupled directly one or morecircuit components, such as, for example, an OLED display 2388.

The boost converter 2318 is coupled to one or more step-down convertersto provide voltages below the boosted voltage level. A first voltageconverter 2316 is coupled to the boost converter 2318 and provides afirst stepped-down voltage to one or more circuit components. In theillustrated example, the first voltage converter 2316 provides a voltageof 5V. The first voltage converter 2316 is coupled to a rotary positionencoder 2340. A FET switch 2317 is coupled between the first voltageconverter 2316 and the rotary position encoder 2340. The FET switch 2317is controlled by the processor 2306. The processor 2306 opens the FETswitch 2317 to deactivate the position encoder 2340, for example, duringpower intensive operations. The first voltage converter 2316 is coupledto a second voltage converter 2314 configured to provide a secondstepped-down voltage. The second stepped-down voltage comprises, forexample, 3.3V. The second voltage converter 2314 is coupled to aprocessor 2306. In some examples, the boost converter 2318, the firstvoltage converter 2316, and the second voltage converter 2314 arecoupled in a daisy chain configuration. The daisy chain configurationallows the use of smaller, more efficient converters for generatingvoltage levels below the boosted voltage level. The examples, however,are not limited to the particular voltage range(s) described in thecontext of this specification.

FIG. 25 illustrates one aspect of a segmented circuit 2400 configured tomaximize power available for critical and/or power intense functions.The segmented circuit 2400 comprises a battery 2408. The battery 2408 isconfigured to provide a source voltage such as, for example, 12V. Thesource voltage is provided to a plurality of voltage converters 2409,2418. An always-on voltage converter 2409 provides a constant voltage toone or more circuit components, for example, a motion sensor 2422 and asafety processor 2404. The always-on voltage converter 2409 is directlycoupled to the battery 2408. The always-on converter 2409 provides avoltage of 3.3V, for example. The examples, however, are not limited tothe particular voltage range(s) described in the context of thisspecification.

The segmented circuit 2400 comprises a boost converter 2418. The boostconverter 2418 provides a boosted voltage above the source voltageprovided by the battery 2408, such as, for example, 13V. The boostconverter 2418 provides a boosted voltage directly to one or morecircuit components, such as, for example, an OLED display 2488 and amotor controller 2443. By coupling the OLED display 2488 directly to theboost converter 2418, the segmented circuit 2400 eliminates the need fora power converter dedicated to the OLED display 2488. The boostconverter 2418 provides a boosted voltage to the motor controller 2443and the motor 2448 during one or more power intensive operations of themotor 2448, such as, for example, a cutting operation. The boostconverter 2418 is coupled to a step-down converter 2416. The step-downconverter 2416 is configured to provide a voltage below the boostedvoltage to one or more circuit components, such as, for example, 5V. Thestep-down converter 2416 is coupled to, for example, a FET switch 2451and a position encoder 2440. The FET switch 2451 is coupled to theprimary processor 2406. The primary processor 2406 opens the FET switch2451 when transitioning the segmented circuit 2400 to sleep mode and/orduring power intensive functions requiring additional voltage deliveredto the motor 2448. Opening the FET switch 2451 deactivates the positionencoder 2440 and eliminates the power draw of the position encoder 2440.The examples, however, are not limited to the particular voltagerange(s) described in the context of this specification.

The step-down converter 2416 is coupled to a linear converter 2414. Thelinear converter 2414 is configured to provide a voltage of, forexample, 3.3V. The linear converter 2414 is coupled to the primaryprocessor 2406. The linear converter 2414 provides an operating voltageto the primary processor 2406. The linear converter 2414 may be coupledto one or more additional circuit components. The examples, however, arenot limited to the particular voltage range(s) described in the contextof this specification.

The segmented circuit 2400 comprises a bailout switch 2456. The bailoutswitch 2456 is coupled to a bailout door on the surgical instrument 10.The bailout switch 2456 and the safety processor 2404 are coupled to anAND gate 2419. The AND gate 2419 provides an input to a FET switch 2413.When the bailout switch 2456 detects a bailout condition, the bailoutswitch 2456 provides a bailout shutdown signal to the AND gate 2419.When the safety processor 2404 detects an unsafe condition, such as, forexample, due to a sensor mismatch, the safety processor 2404 provides ashutdown signal to the AND gate 2419. In some examples, both the bailoutshutdown signal and the shutdown signal are high during normal operationand are low when a bailout condition or an unsafe condition is detected.When the output of the AND gate 2419 is low, the FET switch 2413 isopened and operation of the motor 2448 is prevented. In some examples,the safety processor 2404 utilizes the shutdown signal to transition themotor 2448 to an off state in sleep mode. A third input to the FETswitch 2413 is provided by a current sensor 2412 coupled to the battery2408. The current sensor 2412 monitors the current drawn by the circuit2400 and opens the FET switch 2413 to shut-off power to the motor 2448when an electrical current above a predetermined threshold is detected.The FET switch 2413 and the motor controller 2443 are coupled to a bankof FET switches 2445 configured to control operation of the motor 2448.

A motor current sensor 2446 is coupled in series with the motor 2448 toprovide a motor current sensor reading to a current monitor 2447. Thecurrent monitor 2447 is coupled to the primary processor 2406. Thecurrent monitor 2447 provides a signal indicative of the current draw ofthe motor 2448. The primary processor 2406 may utilize the signal fromthe motor current 2447 to control operation of the motor, for example,to ensure the current draw of the motor 2448 is within an acceptablerange, to compare the current draw of the motor 2448 to one or moreother parameters of the circuit 2400 such as, for example, the positionencoder 2440, and/or to determine one or more parameters of a treatmentsite. In some examples, the current monitor 2447 may be coupled to thesafety processor 2404.

In some aspects, actuation of one or more handle controls, such as, forexample, a firing trigger, causes the primary processor 2406 to decreasepower to one or more components while the handle control is actuated.For example, in one example, a firing trigger controls a firing strokeof a cutting member. The cutting member is driven by the motor 2448.Actuation of the firing trigger results in forward operation of themotor 2448 and advancement of the cutting member. During firing, theprimary processor 2406 opens the FET switch 2451 to remove power fromthe position encoder 2440. The deactivation of one or more circuitcomponents allows higher power to be delivered to the motor 2448. Whenthe firing trigger is released, full power is restored to thedeactivated components, for example, by closing the FET switch 2451 andreactivating the position encoder 2440.

In some aspects, the safety processor 2404 controls operation of thesegmented circuit 2400. For example, the safety processor 2404 mayinitiate a sequential power-up of the segmented circuit 2400, transitionof the segmented circuit 2400 to and from sleep mode, and/or mayoverride one or more control signals from the primary processor 2406.For example, in the illustrated example, the safety processor 2404 iscoupled to the step-down converter 2416. The safety processor 2404controls operation of the segmented circuit 2400 by activating ordeactivating the step-down converter 2416 to provide power to theremainder of the segmented circuit 2400.

FIG. 26 illustrates one aspect of a power system 2500 comprising aplurality of daisy chained power converters 2514, 2516, 2518 configuredto be sequentially energized. The plurality of daisy chained powerconverters 2514, 2516, 2518 may be sequentially activated by, forexample, a safety processor during initial power-up and/or transitionfrom sleep mode. The safety processor may be powered by an independentpower converter (not shown). For example, in one example, when a batteryvoltage VBATT is coupled to the power system 2500 and/or anaccelerometer detects movement in sleep mode, the safety processorinitiates a sequential start-up of the daisy chained power converters2514, 2516, 2518. The safety processor activates the 13V boost section2518. The boost section 2518 is energized and performs a self-check. Insome examples, the boost section 2518 comprises an integrated circuit2520 configured to boost the source voltage and to perform a self check.A diode D prevents power-up of a 5V supply section 2516 until the boostsection 2518 has completed a self-check and provided a signal to thediode D indicating that the boost section 2518 did not identify anyerrors. In some examples, this signal is provided by the safetyprocessor. The examples, however, are not limited to the particularvoltage range(s) described in the context of this specification.

The 5V supply section 2516 is sequentially powered-up after the boostsection 2518. The 5V supply section 2516 performs a self-check duringpower-up to identify any errors in the 5V supply section 2516. The 5Vsupply section 2516 comprises an integrated circuit 2515 configured toprovide a step-down voltage from the boost voltage and to perform anerror check. When no errors are detected, the 5V supply section 2516completes sequential power-up and provides an activation signal to the3.3V supply section 2514. In some examples, the safety processorprovides an activation signal to the 3.3V supply section 2514. The 3.3Vsupply section comprises an integrated circuit 2513 configured toprovide a step-down voltage from the 5V supply section 2516 and performa self-error check during power-up. When no errors are detected duringthe self-check, the 3.3V supply section 2514 provides power to theprimary processor. The primary processor is configured to sequentiallyenergize each of the remaining circuit segments. By sequentiallyenergizing the power system 2500 and/or the remainder of a segmentedcircuit, the power system 2500 reduces error risks, allows forstabilization of voltage levels before loads are applied, and preventslarge current draws from all hardware being turned on simultaneously inan uncontrolled manner. The examples, however, are not limited to theparticular voltage range(s) described in the context of thisspecification.

In one aspect, the power system 2500 comprises an over voltageidentification and mitigation circuit. The over voltage identificationand mitigation circuit is configured to detect a monopolar returncurrent in the surgical instrument and interrupt power from the powersegment when the monopolar return current is detected. The over voltageidentification and mitigation circuit is configured to identify groundfloatation of the power system. The over voltage identification andmitigation circuit comprises a metal oxide varistor. The over voltageidentification and mitigation circuit comprises at least one transientvoltage suppression diode.

FIG. 27 illustrates one aspect of a segmented circuit 2600 comprising anisolated control section 2602. The isolated control section 2602isolates control hardware of the segmented circuit 2600 from a powersection (not shown) of the segmented circuit 2600. The control section2602 comprises, for example, a primary processor 2606, a safetyprocessor (not shown), and/or additional control hardware, for example,a FET Switch 2617. The power section comprises, for example, a motor, amotor driver, and/or a plurality of motor MOSFETS. The isolated controlsection 2602 comprises a charging circuit 2603 and a rechargeablebattery 2608 coupled to a 5V power converter 2616. The charging circuit2603 and the rechargeable battery 2608 isolate the primary processor2606 from the power section. In some examples, the rechargeable battery2608 is coupled to a safety processor and any additional supporthardware. Isolating the control section 2602 from the power sectionallows the control section 2602, for example, the primary processor2606, to remain active even when main power is removed, provides afilter, through the rechargeable battery 2608, to keep noise out of thecontrol section 2602, isolates the control section 2602 from heavyswings in the battery voltage to ensure proper operation even duringheavy motor loads, and/or allows for real-time operating system (RTOS)to be used by the segmented circuit 2600. In some examples, therechargeable battery 2608 provides a stepped-down voltage to the primaryprocessor, such as, for example, 3.3V. The examples, however, are notlimited to the particular voltage range(s) described in the context ofthis specification.

FIGS. 28A and 28B illustrate another aspect of a control circuit 3000configured to control the powered surgical instrument 10, illustrated inFIGS. 1-18A. As shown in FIGS. 18A, 28B, the handle assembly 14 mayinclude a motor 3014 which can be controlled by a motor driver 3015 andcan be employed by the firing system of the surgical instrument 10. Invarious forms, the motor 3014 may be a DC brushed driving motor having amaximum rotation of, approximately, 25,000 RPM, for example. In otherarrangements, the motor 3014 may include a brushless motor, a cordlessmotor, a synchronous motor, a stepper motor, or any other suitableelectric motor. In certain circumstances, the motor driver 3015 maycomprise an H-Bridge FETs 3019, as illustrated in FIG. 28B, for example.The motor 3014 can be powered by a power assembly 3006, which can bereleasably mounted to the handle assembly 14. The power assembly 3006 isconfigured to supply control power to the surgical instrument 10. Thepower assembly 3006 may comprise a battery which may include a number ofbattery cells connected in series that can be used as the power sourceto power the surgical instrument 10. In such configuration, the powerassembly 3006 may be referred to as a battery pack. In certaincircumstances, the battery cells of the power assembly 3006 may bereplaceable and/or rechargeable. In at least one example, the batterycells can be Lithium-Ion batteries which can be separably couplable tothe power assembly 3006.

Examples of drive systems and closure systems that are suitable for usewith the surgical instrument 10 are disclosed in U.S. Provisional PatentApplication Ser. No. 61/782,866, entitled CONTROL SYSTEM OF A SURGICALINSTRUMENT, and filed Mar. 14, 2013, the entire disclosure of which isincorporated by reference herein in its entirety. For example, theelectric motor 3014 can include a rotatable shaft (not shown) that mayoperably interface with a gear reducer assembly that can be mounted inmeshing engagement with a set, or rack, of drive teeth on alongitudinally-movable drive member. In use, a voltage polarity providedby the battery can operate the electric motor 3014 to drive thelongitudinally-movable drive member to effectuate the end effector 300.For example, the motor 3014 can be configured to drive thelongitudinally-movable drive member to advance a firing mechanism tofire staples into tissue captured by the end effector 300 from a staplecartridge assembled with the end effector 300 and/or advance a cuttingmember to cut tissue captured by the end effector 300, for example.

As illustrated in FIGS. 28A and 28B and as described below in greaterdetail, the power assembly 3006 may include a power managementcontroller 3016 which can be configured to modulate the power output ofthe power assembly 3006 to deliver a first power output to power themotor 3014 to advance the cutting member while the interchangeable shaftassembly 200 is coupled to the handle assembly 14 and to deliver asecond power output to power the motor 3014 to advance the cuttingmember while the interchangeable shaft assembly 200 is coupled to thehandle assembly 14, for example. Such modulation can be beneficial inavoiding transmission of excessive power to the motor 3014 beyond therequirements of an interchangeable shaft assembly that is coupled to thehandle assembly 14.

The shaft assembly 200 may include the shaft PCBA 3031 which includesthe shaft assembly controller 3022 which can communicate with the powermanagement controller 3016 through an interface (e.g., interface 3024 ofFIG. 29) while the shaft assembly 200 and the power assembly 3006 arecoupled to the handle assembly 14. For example, the interface maycomprise a first interface portion 3025 which may include one or moreelectric connectors for coupling engagement with corresponding shaftassembly electric connectors and a second interface portion 3027 whichmay include one or more electric connectors for coupling engagement withcorresponding power assembly electric connectors to permit electricalcommunication between the shaft assembly controller 3022 and the powermanagement controller 3016 while the shaft assembly 200 and the powerassembly 3006 are coupled to the handle assembly 14. One or morecommunication signals can be transmitted through the interface tocommunicate one or more of the power requirements of the attachedinterchangeable shaft assembly 200 to the power management controller3016. In response, the power management controller 3016 may modulate thepower output of the battery of the power assembly 3006, as describedbelow in greater detail, in accordance with the power requirements ofthe attached shaft assembly 200. In certain circumstances, one or moreof the electric connectors may comprise switches which can be activatedafter mechanical coupling engagement of the handle assembly 14 to theshaft assembly 200 and/or to the power assembly 3006 to allow electricalcommunication between the shaft assembly controller 3022 and the powermanagement controller 3016.

In certain circumstances, the interface can facilitate transmission ofthe one or more communication signals between the power managementcontroller 3016 and the shaft assembly controller 3022 by routing suchcommunication signals through a main controller 3017 residing in thehandle assembly 14, for example. In other circumstances, the interfacecan facilitate a direct line of communication between the powermanagement controller 3016 and the shaft assembly controller 3022through the handle assembly 14 while the shaft assembly 200 and thepower assembly 3006 are coupled to the handle assembly 14.

In one instance, the main microcontroller 3017 may be any single core ormulticore processor such as those known under the trade name ARM Cortexby Texas Instruments. In one instance, the surgical instrument 10 (FIGS.1-4) may comprise a power management controller 3016 such as, forexample, a safety microcontroller platform comprising twomicrocontroller-based families such as TMS570 and RM4x known under thetrade name Hercules ARM Cortex R4, also by Texas Instruments.Nevertheless, other suitable substitutes for microcontrollers and safetyprocessor may be employed, without limitation. In one instance, thesafety processor 2004 (FIG. 21A) may be configured specifically for IEC61508 and ISO 26262 safety critical applications, among others, toprovide advanced integrated safety features while delivering scalableperformance, connectivity, and memory options.

In certain instances, the microcontroller 3017 may be an LM 4F230H5QR,available from Texas Instruments, for example. In at least one example,the Texas Instruments LM4F230H5QR is an ARM Cortex-M4F Processor Corecomprising on-chip memory of 256 KB single-cycle flash memory, or othernon-volatile memory, up to 40 MHz, a prefetch buffer to improveperformance above 40 MHz, a 32 KB single-cycle serial random accessmemory (SRAM), internal read-only memory (ROM) loaded withStellarisWare® software, 2 KB electrically erasable programmableread-only memory (EEPROM), one or more pulse width modulation (PWM)modules, one or more quadrature encoder inputs (QEI) analog, one or more12-bit Analog-to-Digital Converters (ADC) with 12 analog input channels,among other features that are readily available for the productdatasheet. The present disclosure should not be limited in this context.

The power assembly 3006 may include a power management circuit which maycomprise the power management controller 3016, a power modulator 3038,and a current sense circuit 3036. The power management circuit can beconfigured to modulate power output of the battery based on the powerrequirements of the shaft assembly 200 while the shaft assembly 200 andthe power assembly 3006 are coupled to the handle assembly 14. Forexample, the power management controller 3016 can be programmed tocontrol the power modulator 3038 of the power output of the powerassembly 3006 and the current sense circuit 3036 can be employed tomonitor power output of the power assembly 3006 to provide feedback tothe power management controller 3016 about the power output of thebattery so that the power management controller 3016 may adjust thepower output of the power assembly 3006 to maintain a desired output.

It is noteworthy that the power management controller 3016 and/or theshaft assembly controller 3022 each may comprise one or more processorsand/or memory units which may store a number of software modules.Although certain modules and/or blocks of the surgical instrument 10 maybe described by way of example, it can be appreciated that a greater orlesser number of modules and/or blocks may be used. Further, althoughvarious instances may be described in terms of modules and/or blocks tofacilitate description, such modules and/or blocks may be implemented byone or more hardware components, e.g., processors, Digital SignalProcessors (DSPs), Programmable Logic Devices (PLDs), ApplicationSpecific Integrated Circuits (ASICs), circuits, registers and/orsoftware components, e.g., programs, subroutines, logic and/orcombinations of hardware and software components.

In certain instances, the surgical instrument 10 may comprise an outputdevice 3042 which may include one or more devices for providing asensory feedback to a user. Such devices may comprise, for example,visual feedback devices (e.g., an LCD display screen, LED indicators),audio feedback devices (e.g., a speaker, a buzzer) or tactile feedbackdevices (e.g., haptic actuators). In certain circumstances, the outputdevice 3042 may comprise a display 3043 which may be included in thehandle assembly 14. The shaft assembly controller 3022 and/or the powermanagement controller 3016 can provide feedback to a user of thesurgical instrument 10 through the output device 3042. The interface(e.g. interface 3024 of FIG. 29) can be configured to connect the shaftassembly controller 3022 and/or the power management controller 3016 tothe output device 3042. The reader will appreciate that the outputdevice 3042 can instead be integrated with the power assembly 3006. Insuch circumstances, communication between the output device 3042 and theshaft assembly controller 3022 may be accomplished through the interfacewhile the shaft assembly 200 is coupled to the handle assembly 14.

FIG. 29 is a block diagram the surgical instrument of FIG. 1illustrating interfaces (collectively 3024) between the handle assembly14 and the power assembly 3006 and between the handle assembly 14 andthe interchangeable shaft assembly 200. As shown in FIG. 29, the powerassembly 3006 may include a power management circuit 3034 which maycomprise the power management controller 3016, a power modulator 3038, acurrent sense circuit 3036 and a power assembly connector 3032. Thepower management circuit 3034 can be configured to modulate power outputof the battery 3007 based on the power requirements of the shaftassembly 200 while the shaft assembly 200 and the power assembly 3006are coupled to the handle assembly 14. For example, the power managementcontroller 3016 can be programmed to control the power modulator 3038 ofthe power output of the power assembly 3006 and the current sensecircuit 3036 can be employed to monitor power output of the powerassembly 3006 to provide feedback to the power management controller3016 about the power output of the battery 3007 so that the powermanagement controller 3016 may adjust the power output of the powerassembly 3006 to maintain a desired output. The power assembly connector3032 is configured to connect to the power assembly connector 3030 ofthe handle assembly 14 at the interface 3027 to connect the powerassembly 3006 to the handle assembly 14.

The shaft assembly 200 includes the shaft assembly controller 3022 and ashaft assembly connector 3028. The shaft assembly connector 3028 isconfigured to connect to the shaft assembly connector 3026 of the handleassembly 14 at the interface 3025 to connect the shaft assembly 200 tothe handle assembly 14. As shown in FIG. 29, the handle assembly 14 mayinclude the main microcontroller 3017 and the output device 3042 whichcomprises the display 3043.

As described hereinabove, various components may cooperate to assist inthe control of a motor of a powered surgical instrument. For example,for the powered surgical instrument 10, the motor current sensor 2046measures the current being delivered to the motor 2048 and delivers aninput signal representative of the measured current to the mainprocessor 2006, which in turn applies pulse width modulation signals tothe motor controller 2043, which in turn provides control signals to thegate terminals of the FETS 2044 to control the amount of currentdelivered to the motor 2048 over time from the battery 2008, as well asthe direction of rotation of the motor 2048. One motor current sensor2046 may be utilized to measure the current being delivered to the motor2048 when the motor is rotating in a first direction and another motorcurrent sensor 2046 may be utilized to measure the current beingdelivered to the motor 2048 when the motor is rotating in a seconddirection. Collectively, such components may be considered to form aportion of a control circuit/system or a motor control circuit/system.In various embodiments, in order to measure the current being deliveredto the motor 2048, the motor current sensor 2046 is positioned tomeasure the current flowing in the H-bridge circuit (the H-bridgecircuit includes the FETS 2044 and allows a voltage to be applied acrossthe motor 2048 in either direction to allow the motor 2048 to rotate ina first direction and a second direction) between the motor 2048 and aFET 2044 which is upstream to the motor 2048. The measured current canbe utilized to control the motor 2048, and by extension, to control aforce applied to the firing drive system 80 of the powered surgicalinstrument 10.

In practice, it is relatively difficult to position a motor currentsensor 2046 to measure the current flowing in the H-bridge circuitbetween the motor 2048 and a FET 2044 which is upstream to the motor2048. Therefore, according to various embodiments, it is desired toutilize a current other than the current measured in the H-bridgecircuit to control the motor 2048. For example, in lieu of utilizing thecurrent measured in the H-bridge circuit as described hereinabove, aforce measured at another point in the surgical instrument 10 can beutilized to control the motor 2048.

FIG. 30 illustrates a simplified representation of various electricalcomponents of a surgical stapler 3100 according to various embodiments.According to various embodiments, the surgical stapler 3100 includes adrive system, a handle assembly, an electric motor 3102, a battery 3104,and a control system. The drive system, which is not shown in FIG. 30for purposes of simplicity, may be similar or identical to the firingdrive system 80. The handle assembly, which is not shown in FIG. 30 forpurposes of simplicity, may be similar or identical to the handleassembly 14. The electric motor 3102 is mechanically coupled to thedrive system, and may be similar or identical to the motor 2048. Thebattery 3104 is electrically couplable to the electric motor 3102, andmay be similar or identical to the battery 2008. The control system iselectrically connected to the electric motor 3102, and includes anH-bridge circuit and a plurality of sensors. The plurality of sensorsare not shown in FIG. 30 for purposes of simplicity and will bedescribed in more detail hereinbelow with respect to FIG. 31. TheH-bridge circuit which includes a first switching device 3110, a secondswitching device 3112, a third switching device 3114 and a fourthswitching device 3116. The first, second, third and fourth switchingdevices 3110-3116 may be any suitable type of switching devices, and maybe similar or identical to the FETS 2044. The H-bridge circuit alsodefines a high side and a low side relative to the electric motor 3102.The high side includes first and second legs, with the first switchingdevice 3110 being part of the first leg and the second switching device3112 being part of the second leg as known in the art. The low sideincludes third and fourth legs, with the third switching device 3114being part of the third leg and the fourth switching device 316 beingpart of the fourth leg. The high side of the H-bridge circuit isconsidered the upstream side of the H-bridge circuit and the low side ofthe H-bridge circuit is considered the downstream side of the H-bridgecircuit. The electric motor 3102 is electrically couplable to thebattery 3104 via the H-bridge circuit.

In “general” operation, when the first and fourth switching devices3110, 3116 are “closed” and the second and third switching devices 3112,3114 are “open”, the electric motor 3102 is able to draw current fromthe battery 3104 and rotate in a first direction (e.g., a directionwhich causes a component of the drive system to advance distally). Forthis condition, the path of the current is from the positive terminal ofthe battery 3104, through the first switching device 3110, through theelectric motor 3102, through the fourth switching device 3116 and backto the negative terminal of the battery 3104. Similarly, when the secondand third switching devices 3112, 3114 are “closed” and the first andfourth switching devices 3110, 3116 are “open”, the electric motor 3102is able to draw current from the battery 3104 and rotate in a seconddirection (e.g., a direction which causes a component of the drivesystem to retract proximally). For this condition, the path of thecurrent is from the positive terminal of the battery 3104, through thesecond switching device 3112, through the electric motor 3102, throughthe third switching device 3114 and back to the negative terminal of thebattery 3104. As described in more detail hereinbelow, one or moreforces imparted on or by one or more components of the drive system canbe utilized to control the electric motor 3102.

FIG. 31 illustrates a simplified representation of various electricaland mechanical components of the surgical stapler 3100 according tovarious embodiments. The drive system of the surgical stapler 3100includes the movable drive member 120. For purposes of simplicity, themovable drive member 120 is not shown in FIG. 31. The handle assembly ofthe surgical stapler 3100 includes a frame 3120 configured to receiveand/or support the movable drive member 120. The frame 3120 may besimilar or identical to the frame 20 which, as described hereinabovewith respect to FIG. 4, operably supports the movable drive member 120of the firing drive system 80. The frame 3120 defines a receptacle 3122which operates to help support the movable drive member 120. As shown inFIG. 31, the surgical stapler 3100 may also include a first sensor 3106positioned on an exterior surface of the frame 3120 and a second sensor3108 (shown as dashed lines) positioned on an opposite exterior surfaceof the frame 3120. The first and second sensors 3106, 3108 may beconsidered as part of the control system and may be any suitable type ofsensors configured to sense a force applied to or imparted on the frame3120 by the movable drive member 120. According to various embodiments,the first and second sensors 3106, 3108 are embodied as strain gauges.

In operation, when the first and fourth switching devices 3110, 3116 are“closed” and the second and third switching devices 3112, 3114 are“open”, the electric motor 3102 is able to draw current from the battery3104 and rotate in a first direction which causes the movable drivemember 120 to advance distally. As the movable drive member 120 advancesdistally, it applies or imparts a force on the frame 3120. The force maybe sensed/measured by the first sensor 3106 and/or the second sensor3108. Responsive to the sensed force, the first sensor 3106 may output asignal which is indicative of the magnitude of the force applied to orimparted on the frame 3120, and the second sensor 3108 may output asignal which is indicative of the magnitude of the force applied to orimparted on the frame 3120. The output signals from the first and/orsecond sensors 3106, 3108 may be input to the main processor 2006 tocontrol the electric motor 3102, and by extension, to control a forceapplied to the drive system of the surgical stapler 3100 when theelectric motor 3102 is operating in the first direction. Similarly, whenthe second and third switching devices 3112, 3114 are “closed” and thefirst and fourth switching devices 3110, 3116 are “open”, the electricmotor 3102 is able to draw current from the battery 3104 and rotate in asecond direction which causes the movable drive member 120 to retractproximally. As the movable drive member 120 retracts proximally, itapplies or imparts a force on the frame 3120. The force may besensed/measured by the first sensor 3106 and/or the second sensor 3108.Responsive to the sensed force, the first sensor 3106 may output asignal which is indicative of the magnitude of the force applied to orimparted on the frame 3120, and the second sensor 3108 may output asignal which is indicative of the magnitude of the force applied to orimparted on the frame 3120. The output signals from the first and/orsecond sensors 3106, 3108 may be input to the main processor 2006 tocontrol the electric motor 3102, and by extension, to control a forceapplied to the drive system of the surgical stapler 3100 when theelectric motor 3102 is operating in the second direction.

Although only two sensors 3106, 3108 are shown in FIG. 31, it will beappreciated that the control system may include any number of sensorspositioned on the frame 3120. For example, as described in more detailhereinbelow with respect to FIG. 32, a sensor may be positioned on asurface of the receptacle 3122 of the frame 3120.

FIG. 32 illustrates a simplified representation of a surgical stapler3200 according to various embodiments. The surgical stapler 3200 issimilar to the surgical stapler 3100 in that it includes the drivesystem, the handle assembly, the electric motor and the battery, but isdifferent. As shown in FIG. 32, the drive system includes the drive gear86 and the movable drive member 120. For the surgical stapler 3200, thereceptacle 3222 of the frame 3120 is modified to make it a slightlyflexible beam, and the control system includes a sensor 3206 which ispositioned on a surface of the receptacle 3222. For purposes ofsimplicity only portions of the frame 3120 are shown in FIG. 32,including the receptacle 3222 and bushing blocks 3224. The sensor 3206may be any suitable type of sensor configured to sense a force (e.g., athrust force) applied to or imparted on the receptacle 3222 by themovable drive member 120. According to various embodiments, the sensor3206 is embodied as a strain gauge. Although only one sensor 3206 isshown in FIG. 32, it will be appreciated that the control system mayinclude any number of sensors positioned on the receptacle 3122.

In operation, when the first and fourth switching devices 3110, 3116 are“closed” and the second and third switching devices 3112, 3114 are“open”, the electric motor 3102 is able to draw current from the battery3104 and rotate in a first direction which causes the movable drivemember 120 to advance distally. As the movable drive member 120 advancesdistally, it applies or imparts a force on the receptacle 3222. Theforce may be sensed/measured by the sensor 3206. Responsive to thesensed force, the sensor 3206 may output a signal which is indicative ofthe magnitude of the force applied to or imparted on the receptacle3222. The output signal from the sensor 3206 may be input to the mainprocessor 2006 to control the electric motor 3102, and by extension, tocontrol a force applied to the drive system of the surgical stapler 3100when the electric motor 3102 is operating in the first direction.Similarly, when the second and third switching devices 3112, 3114 are“closed” and the first and fourth switching devices 3110, 3116 are“open”, the electric motor 3102 is able to draw current from the battery3104 and rotate in a second direction which causes the movable drivemember 120 to retract proximally. As the movable drive member 120retracts proximally, it applies or imparts a force (e.g., a thrustforce) on the receptacle 3222. The force may be sensed/measured by thesensor 3206. Responsive to the sensed force, the sensor 3206 may outputa signal which is indicative of the magnitude of the force applied to orimparted on the receptacle 3222. The output signal from the sensor 3206may be input to the main processor 2006 to control the electric motor3102, and by extension, to control a force applied to the drive systemof the surgical stapler 3100 when the electric motor 3102 is operatingin the second direction.

FIG. 33 illustrates a simplified representation of a surgical stapler3300 according to various embodiments. The surgical stapler 3300 issimilar to the surgical stapler 3200 in that it includes the drivesystem, the handle assembly, the electric motor and the battery, but isdifferent. As shown in FIG. 33, the drive system includes the drive gear86, the movable drive member 120 and a shaft 3326 which is mechanicallycoupled to the drive gear 86 and supported by the bushing block portions3324. For purposes of simplicity only portions of the frame 3120 areshown in FIG. 33, including the receptacle 3322 and bushing blocks 3324.For the surgical stapler 3300, one of the bushing block portions 3324 ofthe frame 3120 is modified to make it a slightly flexible beam, and thecontrol system includes a sensor 3306 which is positioned on the surfaceof the modified bushing block portion 3324. The sensor 3306 may be anysuitable type of sensor configured to sense a force (e.g., a bendingforce) applied to or imparted on the bushing block portion 3324 by theshaft 3326. According to various embodiments, the sensor 3306 isembodied as a strain gauge. Although only one bushing block portion 3324is shown as being modified in FIG. 33, it will be appreciated that bothbushing block portions 3324 may be modified to make them slightlyflexible beams. For such embodiments, the control system would includesensors positioned on the surfaces of the respective bushing blockportions 3324. Additionally, it will be appreciated that any number ofsensors may be positioned on or integrated into the building blockportions 3324.

In operation, when the first and fourth switching devices 3110, 3116 are“closed” and the second and third switching devices 3112, 3114 are“open”, the electric motor 3102 is able to draw current from the battery3104 and rotate in a first direction which causes the drive gear 86 andthe shaft 3326 to rotate, and the movable drive member 120 to advancedistally. As the movable drive member 120 advances distally, it appliesor imparts a force (e.g., a bending force) on the shaft 3326 which istransferred to the bushing block portion 3224. The force may besensed/measured by the sensor 3306. Responsive to the sensed force, thesensor 3306 may output a signal which is indicative of the magnitude ofthe force applied to or imparted on the bushing block portion 3224. Theoutput signal from the sensor 3306 may be input to the main processor2006 to control the electric motor 3102, and by extension, to control aforce applied to the drive system of the surgical stapler 3100 when theelectric motor 3102 is operating in the first direction. Similarly, whenthe second and third switching devices 3112, 3114 are “closed” and thefirst and fourth switching devices 3110, 3116 are “open”, the electricmotor 3102 is able to draw current from the battery 3104 and rotate in asecond direction which causes the drive gear 86 and the shaft 3326 torotate, and the movable drive member 120 to proximally. As the movabledrive member 120 retracts proximally, it applies or imparts a force(e.g., a bending force) on the shaft 3326 which is transferred to thebushing block portion 3224. The force may be sensed/measured by thesensor 3306. Responsive to the sensed force, the sensor 3306 may outputa signal which is indicative of the magnitude of the force applied to orimparted on the bushing block portion 3224. The output signal from thesensor 3306 may be input to the main processor 2006 to control theelectric motor 3102, and by extension, to control a force applied to thedrive system of the surgical stapler 3100 when the electric motor 3102is operating in the second direction.

FIG. 34 illustrates a simplified representation of a surgical stapler3400 according to various embodiments. The surgical stapler 3400 issimilar to the surgical stapler 3200 in that it includes the drivesystem, the handle assembly, the electric motor and the battery, but isdifferent. As shown in FIG. 34, the drive system includes the drive gear86, the movable drive member 120 and a shaft 3326 which is mechanicallycoupled to the drive gear 86 and supported by the bushing block portions3424. For purposes of simplicity only portions of the frame 3120 areshown in FIG. 34, including the receptacle 3422 and bushing blocks 3424.For the surgical stapler 3400, one of the bushing block portions 3424includes a three-layer bushing 3428, and the control system includes asensor 3406 coupled to the three-layer bushing 3428. A more detailedrepresentation of the three-layer bushing 3428 in shown in FIG. 35. Afirst layer 3430 of the three-layer bushing 3428 is positioned proximatea surface of the bushing block 3424 and includes a conductive metal. Asecond layer 3432 of the three-layer bushing 3428 is positionedproximate a surface of the shaft 3326 and also includes a conductivemetal. The third layer 3434 of the three-layer bushing 3428 ispositioned between the first and second layers 3430, 3432, and includesa compressive material which is embedded with conductive particles. Whenthe three-layer bushing 3428 experiences a compressive force (e.g., aforce imparted by the drive system), a resistivity between the first andsecond layers 3430, 3432 changes proportionally with the force.

In operation, when the first and fourth switching devices 3110, 3116 are“closed” and the second and third switching devices 3112, 3114 are“open”, the electric motor 3102 is able to draw current from the battery3104 and rotate in a first direction which causes the drive gear 86 andthe shaft 3326 to rotate, and the movable drive member 120 to advancedistally. As the movable drive member 120 advances distally, it appliesor imparts a force on the shaft 3326 which is transferred to thethree-layer bushing 3428. The resultant force causes a compression ofthe three-layer bushing 3428 which in turn changes the resistivitybetween the first and second layers 3430, 3432. The change inresistivity between the first and second layers 3430, 3432 issensed/measured by the sensor 3406. Responsive to the sensed change inresistivity, the sensor 3406 may output a signal which is indicative ofthe magnitude of the force applied to or imparted on the three-layerbushing 3428. The output signal from the sensor 3206 may be input to themain processor 2006 to control the electric motor 3102, and byextension, to control a force applied to the drive system of thesurgical stapler 3100 when the electric motor 3102 is operating in thefirst direction. Similarly, when the second and third switching devices3112, 3114 are “closed” and the first and fourth switching devices 3110,3116 are “open”, the electric motor 3102 is able to draw current fromthe battery 3104 and rotate in a second direction which causes the drivegear 86 and the shaft 3326 to rotate, and the movable drive member 120to retract proximally. As the movable drive member 120 retractsproximally, it applies or imparts a force on the shaft 3326 which istransferred to the three-layer bushing 3428. The resultant force causesa compression of the three-layer bushing 3428 which in turn changes theresistivity between the first and second layers 3430, 3432. The changein resistivity between the first and second layers 3430, 3432 issensed/measured by the sensor 3406. Responsive to the sensed change inresistivity, the sensor 3406 may output a signal which is indicative ofthe magnitude of the force applied to or imparted on the three-layerbushing 3428. The output signal from the sensor 3206 may be input to themain processor 2006 to control the electric motor 3102, and byextension, to control a force applied to the drive system of thesurgical stapler 3100 when the electric motor 3102 is operating in thesecond direction.

Although only one three-layer bushing 3428 is shown in FIG. 34, it willbe appreciated that both bushing block portions 3424 may includethree-layer bushings 3428. For such embodiments, the control system mayinclude an additional sensor 3406 coupled to the additional three-layerbushing 3428. Additionally, it will be appreciated that the sensors 3406may be positioned proximate to, on or integrated into the building blockportions 3424.

FIG. 36 illustrates a simplified representation of a surgical stapler3600 according to various embodiments. The surgical stapler 3600 issimilar to the surgical stapler 3100 in that it includes the drivesystem, the handle assembly, the electric motor and the battery, but isdifferent. As shown in FIG. 36, the drive system includes the drive gear86, the movable drive member 120 and an elongated shaft 3626 which ismechanically coupled to the drive gear 86, is supported by the bushingblock portions 3624 and extends past one of the bushing block portions3624. The shaft 3626 is elongated such that any bending of the shaft3626 resulting from a force applied thereto by the drive system willcause a magnified bending of an end of the shaft 3626. For purposes ofsimplicity only portions of the frame 3120 are shown in FIG. 36,including the receptacle 3622 and bushing blocks 3624. The surgicalstapler 3600 also includes a magnet 3628 connected to an end of theshaft 3626 and a plurality of sensors 3606 surrounding the magnet 3628and the end of the shaft 3626. The sensors 3606 are configured to sensea deviation or bending of the end of the shaft 3626 from a centeredposition of the shaft 3626, and may be considered part of the controlsystem. The sensors 3606 may be any suitable type of sensors and may bepositioned at any suitable location on or within the surgical stapler.For example, according to various embodiments, the sensors 3606 areembodied as Hall-effect sensors which are positioned on or proximate theframe 3120 (e.g., proximate the bushing block 3624). Although threesensors 3606 are shown in FIG. 36, it will be appreciated that thesurgical instrument 3600 may include any number of sensors 3606configured to sense a deviation or bending of the end of the shaft 3626from a centered position of the shaft 3626. Additionally, although onlyone end of the shaft 3626 is shown as being extended past a bushingblock 3624 in FIG. 36, it will be appreciated that both ends of theshaft 3626 may be extended, both ends may have a magnet 3628 connectedthereto, and both magnets 3628 may be surrounded by a plurality ofsensors 3606.

In operation, when the first and fourth switching devices 3110, 3116 are“closed” and the second and third switching devices 3112, 3114 are“open”, the electric motor 3102 is able to draw current from the battery3104 and rotate in a first direction which causes the drive gear 86 andthe shaft 3626 to rotate, and the movable drive member 120 to advancedistally. As the movable drive member 120 advances distally, it appliesor imparts a force on the shaft 3626. The force applied to the shaft3626 causes a bending at the end of the shaft 3626, which causes themagnet 3628 to move closer to one of the sensors 3606 and further awayfrom the other sensors 3606. The respective changes in the distance fromthe magnet 3628 to the respective sensors 3606 may be sensed/measured bythe sensors 3606. Responsive to the respective sensed changes indistance, the sensors 3606 may each output signals which are indicativeof the magnitude of the force applied to or imparted on the shaft 3626.The respective output signals from the sensors 3606 may be input to themain processor 2006 to control the electric motor 3102, and byextension, to control a force applied to the drive system of thesurgical stapler 3100 when the electric motor 3102 is operating in thefirst direction. Similarly, when the second and third switching devices3112, 3114 are “closed” and the first and fourth switching devices 3110,3116 are “open”, the electric motor 3102 is able to draw current fromthe battery 3104 and rotate in a second direction which causes the drivegear 86 and the shaft 3326 to rotate, and the movable drive member 120to retract proximally. As the movable drive member 120 retractsproximally, it applies or imparts a force on the shaft 3326, whichcauses the magnet 3628 to move closer to one of the sensors 3606 andfurther away from the other sensors 3606. The respective changes in thedistance from the magnet 3628 to the respective sensors 3606 may besensed/measured by the sensors 3606. Responsive to the respective sensedchanges in distance, the sensors 3606 may each output signals which areindicative of the magnitude of the force applied to or imparted on theshaft 3626. The respective output signals from the sensors 3606 may beinput to the main processor 2006 to control the electric motor 3102, andby extension, to control a force applied to the drive system of thesurgical stapler 3100 when the electric motor 3102 is operating in thesecond direction.

FIG. 37 illustrates various embodiments of a method 3700 for limiting animpact force applied by the surgical stapler. The method 3700 may beimplemented by any of the surgical staplers described herein. Theprocess starts at block 3710, where each of the mass values andstiffness values for components of a system of the surgical stapler areread from one or more memories located in the surgical stapler. Thesystem may be any system of the surgical stapler such as, for example,the closure system 30 or the firing system 80 described hereinabove. Themass values and the stiffness values may be read, for example, by themotor controller 2043 from a memory in the handle assembly 14 and/or amemory in the shaft assembly 200.

From block 3710, the process advances to block 3720, where each of themaximum force values for each state of the surgical stapler are readfrom the one or more memories. The maximum force values may be read, forexample, by the motor controller 2043 from a memory in the handleassembly 14 and/or a memory in the shaft assembly 200. The maximum forcevalues may include, for example, maximum force values for a clampedstate of the surgical stapler, maximum force values for an unclampedstated of the surgical stapler, maximum force values for an articulatingstate of the surgical stapler, maximum force values for a firing stateof the surgical stapler, etc. It will be appreciated that the actionstaken at blocks 3710 and 3720 may occur sequentially, concurrently or ina different order.

From block 3720, the process advances to block 3730, where a currentstate of the surgical stapler is determined. According to variousembodiments, the determination may be based on the read mass values,stiffness values and maximum force values, and may be made by the mainprocessor 2006, the safety processor 2004 or a combination thereof.Additionally, according to various embodiments, once the currentconfiguration of the surgical stapler is determined, an overall massvalue and an overall stiffness value for the system can be determined byadding the respective mass values for each component of the system andadding the respective stiffness values for each component of the system.

From block 3730, the process advances to block 3740, where the electricmotor (e.g., the electric motor 3102) is controlled, based on themaximum force values for the determined state of the surgical stapler,to limit the impact force applied by an end effector (e.g., the endeffector 300) of the surgical stapler. According to various embodiments,for a given determined current state of the surgical stapler, theelectric motor is controlled to control a velocity of one of the systemcomponents (e.g., the knife bar 280) such that the velocity is less thanor equal to the maximum force value for the determined state of thesurgical stapler divided by a square root of a product of the overallmass value and the overall stiffness value for the system of thesurgical stapler.

The above-described process can be repeated any number of times. After agiven state of the surgical instrument has changed to another state(e.g., changed from a clamped state an unclamped state), another overallmass value and another overall stiffness value for the system can bedetermined in the above-described manner, and the electric motor can becontrolled to limit the velocity of one of the system components tolimit the impact force applied by the end effector of the surgicalstapler. By utilizing the above method, it will be appreciated thatexcessive impact forces applied by the end effector to tissue can beprevented, and in-line force sensors and high speed motion control arenot required.

EXAMPLES Example 1

A surgical stapler is provided. The surgical stapler comprises a drivesystem comprising a movable drive member, a handle assembly comprising aframe configured to support the movable drive member therein, anelectric motor mechanically coupled to the drive system, a batteryelectrically couplable to the electric motor, and a control systemelectrically connected to the electric motor. The control systemcomprises a sensor positioned on the frame. The control system isconfigured to control the electric motor based on a force applied to theframe by the movable drive member.

Example 2

The surgical stapler of Example 1, wherein the sensor comprises a straingauge.

Example 3

The surgical stapler of Examples 1 or 2, wherein the sensor ispositioned on an exterior surface of the frame.

Example 4

The surgical stapler of Examples 1, 2 or 3, wherein the sensor isconfigured to sense the force applied to the frame by the movable drivemember.

Example 5

The surgical stapler of Examples 1, 2, 3 or 4, wherein the controlsystem further comprises a plurality of sensors positioned on the frame.

Example 6

A surgical stapler is provided. The surgical stapler comprises a drivesystem comprising a movable drive member, a handle assembly comprising aframe, wherein the frame defines a receptacle configured to support themovable drive member therein, an electric motor mechanically coupled tothe drive system, a battery electrically couplable to the electricmotor, and a control system electrically connected to the battery. Thecontrol system comprises a sensor positioned on the receptacle. Thecontrol system is configured to control the electric motor based on aforce applied to the receptacle by the movable drive member.

Example 7

The surgical stapler of Example 6, wherein the sensor comprises a straingauge.

Example 8

The surgical stapler of Examples 6 or 7, wherein the sensor isconfigured to sense the force applied to the receptacle by the movabledrive member.

Example 9

The surgical stapler of Examples 6, 7 or 8, wherein the control systemfurther comprises a plurality of sensors positioned on the receptacle.

Example 10

A surgical stapler is provided. The surgical stapler comprises a drivesystem, a handle assembly, an electric motor mechanically coupled to thedrive system, a battery electrically couplable to the electric motor,and a control system electrically connected to the electric motor. Thedrive system comprises a movable driving member, a gear mechanicallycoupled with the movable driving member, and a shaft connected to thegear. The handle assembly comprises a bushing block configured tosupport the shaft. The control system comprises a sensor positioned onthe bushing block and is configured to control the electric motor basedon a force applied to the bushing block by the drive system.

Example 11

The surgical stapler of Example 10, wherein the sensor comprises astrain gauge.

Example 12

The surgical stapler of Examples 10 or 11, wherein the sensor isconfigured to sense the force applied to the bushing block by the drivesystem.

Example 13

The surgical stapler of Examples 10, 11 or 12, wherein the handleassembly further comprises a second bushing block configured to supportthe shaft, and the control system further comprises a second sensorpositioned on the second bushing block.

Example 14

A surgical stapler is provided. The surgical stapler comprises a drivesystem, a handle assembly, an electric motor mechanically coupled to thedrive system, a battery electrically couplable to the electric motor,and a control system electrically connected to the electric motor. Thedrive system comprises a movable drive member, a gear mechanicallycoupled with the movable drive member, and a shaft connected to thegear. The handle assembly comprises a bushing block configured tosupport the shaft, wherein the bushing block comprises a three-layerbushing. The control system comprises a sensor coupled to thethree-layered bushing. The control system is configured to control theelectric motor based on a force applied to the three-layer bushing bythe drive system.

Example 15

The surgical stapler of Example 14, wherein the sensor is configured tosense a compression force applied to the three-layer bushing by thedrive system.

Example 16

The surgical stapler of Examples 14 or 15, wherein, one, the handleassembly further comprises a second bushing block configured to supportthe shaft, wherein the second bushing block comprises a secondthree-layer bushing, and, two, the control system further comprises asecond sensor coupled to the second three-layer bushing.

Example 17

A surgical stapler is provided. The surgical stapler comprises a drivesystem, wherein the drive system comprises a movable rack, a gearmechanically coupled with the movable rack, and a shaft connected to thegear. The surgical stapler further comprises a magnet connected to anend of the shaft, a handle assembly comprising a frame configured tosupport the shaft, an electric motor mechanically coupled to the drivesystem, a battery electrically couplable to the electric motor, and acontrol system electrically connected to the electric motor. The controlsystem comprises an array of sensors surrounding the magnet, and thecontrol system is configured to control the electric motor based on aforce applied to shaft.

Example 18

The surgical stapler of Example 17, wherein the array of sensorscomprises an array of Hall-effect sensors.

Example 19

The surgical stapler of Examples 17 or 18, wherein the array of sensorsare configured to sense a bending of the end of the shaft.

Example 20

A method for limiting an impact force applied by a surgical stapler isprovided. The method comprises reading mass values and stiffness valuesfor components of a system from one or more memories of the surgicalstapler, reading maximum force values from one or more memories for eachstate of the surgical stapler, determining a current state of thesurgical stapler, and controlling an electric motor of the surgicalstapler to limit the impact force applied by an end effector thesurgical stapler based on the maximum force values for the determinedstate of the surgical stapler.

Example 21

The method of Example 20, wherein reading the mass values and stiffnessvalues comprises reading the values from at least one of the following:a memory in a handle assembly of the surgical stapler, and a memory in ashaft assembly of the surgical stapler.

Example 22

The method of Examples 20 or 21, wherein reading the maximum forcevalues comprises reading at least one of the following: a maximum forcevalue for a clamped state of the surgical stapler, a maximum force valuefor an unclamped state of the surgical stapler, a maximum force valuefor an articulated state of the surgical stapler, and a maximum forcevalue for a firing state of the surgical stapler.

Example 23

The method of Examples 20, 21 or 22, further comprising determining anoverall mass value and an overall stiffness value for at least one ofthe following: a closure system of the surgical stapler, and a firingsystem of the surgical stapler.

Example 24

The method of Examples 20, 21, 22 or 23, wherein controlling theelectric motor comprises, for the determined state of the surgicalstapler, controlling the electric motor such that the velocity of one ofthe system components is less than or equal to the maximum force valuefor the determined state of the surgical stapler divided by a squareroot of a product of the overall mass value and the overall stiffnessvalue for the system of the surgical stapler.

Example 25

The method of Examples 23 or 24, further comprising determining at leastone of the following after the state of the surgical stapler is changed:another overall mass value for the system of the surgical stapler, andanother overall stiffness value for the system of the surgical stapler.

The entire disclosures of:

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U.S. Pat. No. 7,000,818, entitled SURGICAL STAPLING INSTRUMENT HAVINGSEPARATE DISTINCT CLOSING AND FIRING SYSTEMS, which issued on Feb. 21,2006;

U.S. Pat. No. 7,422,139, entitled MOTOR-DRIVEN SURGICAL CUTTING ANDFASTENING INSTRUMENT WITH TACTILE POSITION FEEDBACK, which issued onSep. 9, 2008;

U.S. Pat. No. 7,464,849, entitled ELECTRO-MECHANICAL SURGICAL INSTRUMENTWITH CLOSURE SYSTEM AND ANVIL ALIGNMENT COMPONENTS, which issued on Dec.16, 2008;

U.S. Pat. No. 7,670,334, entitled SURGICAL INSTRUMENT HAVING ANARTICULATING END EFFECTOR, which issued on Mar. 2, 2010;

U.S. Pat. No. 7,753,245, entitled SURGICAL STAPLING INSTRUMENTS, whichissued on Jul. 13, 2010;

U.S. Pat. No. 8,393,514, entitled SELECTIVELY ORIENTABLE IMPLANTABLEFASTENER CARTRIDGE, which issued on Mar. 12, 2013;

U.S. patent application Ser. No. 11/343,803, entitled SURGICALINSTRUMENT HAVING RECORDING CAPABILITIES; now U.S. Pat. No. 7,845,537;

U.S. patent application Ser. No. 12/031,573, entitled SURGICAL CUTTINGAND FASTENING INSTRUMENT HAVING RF ELECTRODES, filed Feb. 14, 2008;

U.S. patent application Ser. No. 12/031,873, entitled END EFFECTORS FORA SURGICAL CUTTING AND STAPLING INSTRUMENT, filed Feb. 15, 2008, nowU.S. Pat. No. 7,980,443;

U.S. patent application Ser. No. 12/235,782, entitled MOTOR-DRIVENSURGICAL CUTTING INSTRUMENT, now U.S. Pat. No. 8,210,411;

U.S. patent application Ser. No. 12/249,117, entitled POWERED SURGICALCUTTING AND STAPLING APPARATUS WITH MANUALLY RETRACTABLE FIRING SYSTEM,now U.S. Pat. No. 8,608,045;

U.S. patent application Ser. No. 12/647,100, entitled MOTOR-DRIVENSURGICAL CUTTING INSTRUMENT WITH ELECTRIC ACTUATOR DIRECTIONAL CONTROLASSEMBLY, filed Dec. 24, 2009; now U.S. Pat. No. 8,220,688;

U.S. patent application Ser. No. 12/893,461, entitled STAPLE CARTRIDGE,filed Sep. 29, 2012, now U.S. Pat. No. 8,733,613;

U.S. patent application Ser. No. 13/036,647, entitled SURGICAL STAPLINGINSTRUMENT, filed Feb. 28, 2011, now U.S. Pat. No. 8,561,870;

U.S. patent application Ser. No. 13/118,241, entitled SURGICAL STAPLINGINSTRUMENTS WITH ROTATABLE STAPLE DEPLOYMENT ARRANGEMENTS, now U.S. Pat.No. 9,072,535;

U.S. patent application Ser. No. 13/524,049, entitled ARTICULATABLESURGICAL INSTRUMENT COMPRISING A FIRING DRIVE, filed on Jun. 15, 2012;now U.S. Pat. No. 9,101,358;

U.S. patent application Ser. No. 13/800,025, entitled STAPLE CARTRIDGETISSUE THICKNESS SENSOR SYSTEM, filed on Mar. 13, 2013, now U.S. PatentApplication Publication No. 2014/0263551;

U.S. patent application Ser. No. 13/800,067, entitled STAPLE CARTRIDGETISSUE THICKNESS SENSOR SYSTEM, filed on Mar. 13, 2013, now U.S. PatentApplication Publication No. 2014/0263552;

U.S. Patent Application Publication No. 2007/0175955, entitled SURGICALCUTTING AND FASTENING INSTRUMENT WITH CLOSURE TRIGGER LOCKING MECHANISM,filed Jan. 31, 2006; and

U.S. Patent Application Publication No. 2010/0264194, entitled SURGICALSTAPLING INSTRUMENT WITH AN ARTICULATABLE END EFFECTOR, filed Apr. 22,2010, now U.S. Pat. No. 8,308,040, are hereby incorporated by referenceherein.

Although the various embodiments of the devices have been describedherein in connection with certain disclosed embodiments, manymodifications and variations to those embodiments may be implemented.Also, where materials are disclosed for certain components, othermaterials may be used. Furthermore, according to various embodiments, asingle component may be replaced by multiple components, and multiplecomponents may be replaced by a single component, to perform a givenfunction or functions. The foregoing description and following claimsare intended to cover all such modification and variations.

The devices disclosed herein can be designed to be disposed of after asingle use, or they can be designed to be used multiple times. In eithercase, however, the device can be reconditioned for reuse after at leastone use. Reconditioning can include any combination of the steps ofdisassembly of the device, followed by cleaning or replacement ofparticular pieces, and subsequent reassembly. In particular, the devicecan be disassembled, and any number of the particular pieces or parts ofthe device can be selectively replaced or removed in any combination.Upon cleaning and/or replacement of particular parts, the device can bereassembled for subsequent use either at a reconditioning facility, orby a surgical team immediately prior to a surgical procedure. Thoseskilled in the art will appreciate that reconditioning of a device canutilize a variety of techniques for disassembly, cleaning/replacement,and reassembly. Use of such techniques, and the resulting reconditioneddevice, are all within the scope of the present application.

By way of example only, aspects described herein may be processed beforesurgery. First, a new or used instrument may be obtained and whennecessary cleaned. The instrument may then be sterilized. In onesterilization technique, the instrument is placed in a closed and sealedcontainer, such as a plastic or TYVEK (commercially available from E. I.du Pont de Nemours and Company) bag. The container and instrument maythen be placed in a field of radiation that can penetrate the container,such as gamma radiation, x-rays, or high-energy electrons. The radiationmay kill bacteria on the instrument and in the container. The sterilizedinstrument may then be stored in the sterile container. The sealedcontainer may keep the instrument sterile until it is opened in amedical facility. A device also may be sterilized using any othertechnique known in the art, including but not limited to beta or gammaradiation, ethylene oxide, plasma peroxide, or steam.

While this invention has been described as having exemplary designs, thepresent invention may be further modified within the spirit and scope ofthe disclosure. This application is therefore intended to cover anyvariations, uses, or adaptations of the invention using its generalprinciples.

Any patent, publication, or other disclosure material, in whole or inpart, that is said to be incorporated by reference herein isincorporated herein only to the extent that the incorporated materialsdoes not conflict with existing definitions, statements, or otherdisclosure material set forth in this disclosure. As such, and to theextent necessary, the disclosure as explicitly set forth hereinsupersedes any conflicting material incorporated herein by reference.Any material, or portion thereof, that is said to be incorporated byreference herein, but which conflicts with existing definitions,statements, or other disclosure material set forth herein will only beincorporated to the extent that no conflict arises between thatincorporated material and the existing disclosure material.

What is claimed is:
 1. A surgical stapler, comprising: a drive systemcomprising a movable drive member; a handle assembly comprising a frameconfigured to support the movable drive member therein; an electricmotor mechanically coupled to the drive system; a battery electricallycouplable to the electric motor; and a control system electricallyconnected to the electric motor, wherein the control system comprises asensor positioned on the frame, and wherein the control system isconfigured to control the electric motor based on a force applied to theframe by the movable drive member.
 2. The surgical stapler of claim 1,wherein the sensor comprises a strain gauge.
 3. The surgical stapler ofclaim 1, wherein the sensor is positioned on an exterior surface of theframe.
 4. The surgical stapler of claim 1, wherein the sensor isconfigured to sense the force applied to the frame by the movable drivemember.
 5. The surgical stapler of claim 1, wherein the control systemfurther comprises a plurality of sensors positioned on the frame.
 6. Asurgical stapler, comprising: a drive system comprising a movable drivemember; a handle assembly comprising a frame, wherein the frame definesa receptacle configured to support the movable drive member therein; anelectric motor mechanically coupled to the drive system; a batteryelectrically couplable to the electric motor; and a control systemelectrically connected to the battery, wherein the control systemcomprises a sensor positioned on the receptacle, and wherein the controlsystem is configured to control the electric motor based on a forceapplied to the receptacle by the movable drive member.
 7. The surgicalstapler of claim 6, wherein the sensor comprises a strain gauge.
 8. Thesurgical stapler of claim 6, wherein the sensor is configured to sensethe force applied to the receptacle by the movable drive member.
 9. Thesurgical stapler of claim 6, wherein the control system furthercomprises a plurality of sensors positioned on the receptacle.
 10. Asurgical stapler, comprising: a drive system comprising: a movabledriving member; a gear mechanically coupled with the movable drivingmember; and a shaft connected to the gear; a handle assembly comprisinga bushing block configured to support the shaft; an electric motormechanically coupled to the drive system; a battery electricallycouplable to the electric motor; and a control system electricallyconnected to the electric motor, wherein the control system comprises asensor positioned on the bushing block and is configured to control theelectric motor based on a force applied to the bushing block by thedrive system.
 11. The surgical stapler of claim 10, wherein the sensorcomprises a strain gauge.
 12. The surgical stapler of claim 10, whereinthe sensor is configured to sense the force applied to the bushing blockby the drive system.
 13. The surgical stapler of claim 10, wherein: thehandle assembly further comprises a second bushing block configured tosupport the shaft; and the control system further comprises a secondsensor positioned on the second bushing block.
 14. A surgical stapler,comprising: a drive system comprising: a movable drive member; a gearmechanically coupled with the movable drive member; and a shaftconnected to the gear; a handle assembly comprising a bushing blockconfigured to support the shaft, wherein the bushing block comprises athree-layer bushing; an electric motor mechanically coupled to the drivesystem; a battery electrically couplable to the electric motor; and acontrol system electrically connected to the electric motor, wherein thecontrol system comprises a sensor coupled to the three-layered bushing,and wherein the control system is configured to control the electricmotor based on a force applied to the three-layer bushing by the drivesystem.
 15. The surgical stapler of claim 14, wherein the sensor isconfigured to sense a compression force applied to the three-layerbushing by the drive system.
 16. The surgical stapler of claim 14,wherein: the handle assembly further comprises a second bushing blockconfigured to support the shaft, wherein the second bushing blockcomprises a second three-layer bushing; and the control system furthercomprises a second sensor coupled to the second three-layer bushing. 17.A surgical stapler, comprising: a drive system comprising: a movablerack; a gear mechanically coupled with the movable rack; and a shaftconnected to the gear; a magnet connected to an end of the shaft; ahandle assembly comprising a frame configured to support the shaft; anelectric motor mechanically coupled to the drive system; a batteryelectrically couplable to the electric motor; and a control systemelectrically connected to the electric motor, wherein the control systemcomprises an array of sensors surrounding the magnet, and wherein thecontrol system is configured to control the electric motor based on aforce applied to shaft.
 18. The surgical stapler of claim 17, whereinthe array of sensors comprises an array of Hall-effect sensors.
 19. Thesurgical stapler of claim 17, wherein the array of sensors areconfigured to sense a bending of the end of the shaft.
 20. A method forlimiting an impact force applied by a surgical stapler, the methodcomprising: reading mass values and stiffness values for components of asystem from one or more memories of the surgical stapler; readingmaximum force values from one or more memories for each state of thesurgical stapler; determining a current state of the surgical stapler;and controlling an electric motor of the surgical stapler to limit theimpact force applied by an end effector the surgical stapler based onthe maximum force values for the determined state of the surgicalstapler.
 21. The method of claim 20, wherein reading the mass values andstiffness values comprises reading the values from at least one of thefollowing: a memory in a handle assembly of the surgical stapler; and amemory in a shaft assembly of the surgical stapler.
 22. The method ofclaim 20, wherein reading the maximum force values comprises reading atleast one of the following: a maximum force value for a clamped state ofthe surgical stapler; a maximum force value for an unclamped state ofthe surgical stapler; a maximum force value for an articulated state ofthe surgical stapler; and a maximum force value for a firing state ofthe surgical stapler.
 23. The method of claim 20, further comprisingdetermining an overall mass value and an overall stiffness value for atleast one of the following: a closure system of the surgical stapler;and a firing system of the surgical stapler.
 24. The method of claim 23,wherein controlling the electric motor comprises, for the determinedstate of the surgical stapler, controlling the electric motor such thatthe velocity of one of the system components is less than or equal tothe maximum force value for the determined state of the surgical staplerdivided by a square root of a product of the overall mass value and theoverall stiffness value for the system of the surgical stapler.
 25. Themethod of claim 23, further comprising determining at least one of thefollowing after the state of the surgical stapler is changed: anotheroverall mass value for the system of the surgical stapler; and anotheroverall stiffness value for the system of the surgical stapler.